Here goes. But please note the broad categories listed by our OP are prejudicial to me. I therefore am going alphabetical.

Aman--former top purveyor of remote luxury and service with good to excellent food/beverage, now unused to higher occupancy or the competition from urban 5* hotels and therefore having concomitantly less impressive service levels in its current incarnation.

Banyan Tree--luxury light service with Asian inspired architecture and design that pretends it's as good as Mandarin Oriental, even though it rarely comes close.

Belmond--curated collection of authentic, often historic properties or locations/services offering high levels of service and food/beverage, but with some better than others. At its best, more often than not can compete with the best in the world; at its worst, makes you wonder how it qualifies as luxury.

Capella--rapidly changing property list leaves everyone's heads spinning, but usually high end locally inspired architecture with spacious and well appointed rooms/suites offering nice service and good food/beverage...and probably management fees that are way too ambitious!

Como--curated collection of new and historic properties/conversions that operate at good levels of luxury and service but usually at more affordable rates, often with a more casual elegance rather than any traditional formality as with so many other luxury chains.

Conrad--Hilton's version of JW Marriott, offering watered down affordable luxury hotels and resorts, often with lounges that are very popular and a driving reason for stays at very good value but less than personalized service

Dorchester--curated collection of Older World fancy and formal and usually overly traditional type properties that remind everyone of the Gilded Age and outdated traditions with that era. The total repudiation of all things Millenial...except for the see and be seen artifact.

Fairmont--a luxury chain basking in former glory with watered down service and everything else, not always offering luxury these days

Four Seasons--corporate inspired (and sometimes bland) urban luxury hotels and locally inspired more authentic feeling resort properties in almost every major city and resort destination you can think of, blending usually good service that too often seems to come from a recipe book.

GHM--not necessarily luxury but very well run newer and converted properties with Asian sensibilities at less than luxury price points in various locations.

Grand Hyatt--not luxury, even though they can offer good service, too big and convention/conference style corporate hotels for business

Intercontinental--not luxury, even though the Hong Kong property (soon to be Regent again) suggests otherwise

Jumeirah--luxury hotels that are as grandiose in scale as they are in traditional and too often dated design and unnecessary formality, largely centered around the Middle East and a few other cities favored by the affluent from the Middle East

Kempinski--this is luxury lite with more German efficiency than true luxury service

Luxury Collection--a curated collection of some of the world's best historic luxury hotels and palaces offering the height of service and food/beverage, mixed with newer deluxe 4* properties not always being proper luxury offering watered down luxury experiences but usually excellent food/beverage.

Mandarin Oriental--extremely good hard product builds with Asian inspired modern design that doesn't always have a sense of place and too often pretends it is Aman and Peninsula even as it maddeningly and often stupidly doesn't come close to Banyan Tree. Often feels a bit more stiff and formal.

Oberoi--newer luxury hotels built to mimic a bygone era of British/Indian grandeur, offering very high levels of service with a serious dose of formality largely focused around India and the markets nearby frequented by wealthy Indians.

Oetker--Dorchester without as many high end prostitutes and more geographical diversity

One&Only--luxury resorts pretending to be Four Seasons without quite the consistency in good service or corporate feel

Park Hyatt--luxury hotels focused on modern Asian/Scandinavian simplicity and clean design, often offering very good service and food/beverage but with poor housekeeping and outsourcing issues clouding its good reputation and growing portfolio; its use of points makes some foolishly believe it isn't comparable to FS even though it is

Peninsula--Asian inspired design and style and high technology and excellent service ethos in urban centers, often with a serious dose of formality that is better executed than Mandarin Oriental or Four Seasons or St Regis could accomplish. Usually hits the mark, unlike most. They own and manage their own properties, hence they do it better than almost anyone else.

Raffles--these are luxury?

Ritz-Carlton--corporate and bland luxury properties offering good to excellent service entirely contingent on paying up to their Club Level, which is a very nice lounge offering all day dining/snacks and better concierge and executive services. Not many room categories.

Rocco Forte--these are luxury?

Rosewood--ever expanding curated collection of urban center hotels and resort properties, almost becoming an Aman-ish and Aman-lite collection with good to great service, truly impressive hard products, but even better food/beverage than Aman. Its rapid growth might cause it issues much like Four Seasons...

Shangri-La--Asia's version of JW Marriott and Conrad rolled into one, almost Ritz Carlton lite, all of which have nice Clubs

Singita--curated collection of safari and safari-like boutique properties that allow guests to experience the wild and wildlife in supreme comfort and with extremely high levels of service (and usually food/beverage) even in the most remote locations, with both very traditional and very modern architecture and styles to choose from.

Six Senses--rapidly expanding spa/hotel collection of hotel and resort properties and spas that usually try to combine casual luxury with good service at reasonable rates for their locations.

St. Regis--a Gilded Age inspired modern luxury chain known for its butler service and technology, Peninsula lite in terms of overall consistency, with a few traditional but many more modern inspired new and converted properties.

Taj--Indian luxury operator of many converted historic palaces and unique properties at the highest luxury standard with a less known curated collection of luxury properties around the world with very traditional design/ and even outdated decor.

Waldorf Astoria--Hilton's version of St Regis, with less identity or hallmarks other than good to excellent service, a more formal atmosphere and reputation, and lots of older conversions that don't match up well with the brand.