Speaking as a lowly titanium here (near 100 nights but not near $20k spend), my guess, based on the wild variance in people's experiences, is that the ambassadors are overloaded and are prioritizing their time based on the members' spend (or some other metric, spend/night etc).

That would certainly explain why someone who "accidentally" got Ambassador gets zero response.

Although I've been disappointed and occasionally appalled at the way the loyalty program has been managed since the merger, at the hotel level, which is what matters most to me, I have very few complaints. With one possible exception, as a Lifetime Titanium member I have been upgraded to at least a standard suite on every Marriott stay since the merger. The only potential failure was the St. Regis Osaka, where there were several lower level suites open during a brief paid stay, which I am willing to overlook based on the reviews of others on FT whose opinions I respect.

Both the SPG and MR side had IT problems, but I had few issues besides the disclosure of my family's personal data caused by the breach. My biggest complaints were due to use of social media to communicate certain impending changes instead of direct communication with customers and the unwillingness to tell members what the conversion rate from old to new travel packages was until it was too late to make changes.

Off topic:

Honestly, I have received at least the advertised benefits at Fairmont, Hilton, Hyatt and IHG in almost every case. Although many criticize Hilton for lack of elite benefits, I believe I received a suite upgrade on close to 100% of my stays. My best upgrade last year was at the Intercontinental in Osaka when using the certificate that came with my $49 per year credit card. At the Explorist level, there are few benefits for me at Hyatt but I did receive one very nice upgrade at a Park Hyatt last year.

Most of my hotel complaints have been the result of inconsiderate guest behavior of other guests and the failure of the hotel to deal with it appropriately. Examples across different chains would include: loud arguments and parities long past midnight that the hotel wouldn't deal with, allowing excessive cell phone use and large business meetings in the lounge, letting people bring their own speakers to the pool or beach, and a dog that barked for hours in a nearby room. Obviously, those issues can and do happen at any hotel chain.

Although I don't need a lot of personal attention, I do appreciate having lounge access due to the additional staff interaction. In general, I find lounge employees more willing to suggest restaurants that locals frequent, instead of the typical tourist ones, than concierges. When things are less busy, I enjoy the chance to learn and practice my minimal foreign language skills with lounge staff.

Could be. It also could simply be a function of non standardization, or the requests aren't tracked in SFDC yet to be able to really pull metrics.

My ambassador has responded promptly to me. That said, I have reached out 3 total times for tiny things that my Ambassador has handled immediately. It could also be that my ambassador got a set of people like me, who put the DND/MAGC door hangar immediately after check in and need/want nothing else; which means they have more time for the other members who reach out more or have more requests.

But it did. The reason I switched a lot of stays to Marriott from SPG back in 2014 was that it was increasingly difficult to find hotels in certain places. The acquisition worked out well for me, as I went from being far away on LT status to having it as those years and nights now added up.

Absolutely. Plenty of things that Marriott can adopt or learn from from Hyatt.

Improvement by Marriott ... which is very good

Pre-upgraded to One Bedroom Suite at Ritz-Carlton Georgetown
 

I am convinced there are many levels within AMB. Something akin to BA CIV scores. bhrubin likely has CIV of 105 while mine is closer to 0.;):p

To non BA flyers, BA CIV scores is rumored to be between 0 and 105. It started as 0 to 100 but another VVIP level (105) was added later.