I'm titanium and HH Diamond (through status match back in fall '18). For where I was travelling to (western Canada), the only Hilton offerings were HGIs and Hamptons so I didn't actually stay much at all at Hilton. I've only been doing it more often now since the promotion at Marriott was almost non existent for Q4 and there currently isn't one and I did not get a targeted offer. So now I just take advantage of the Hilton bonus and hop around for the 2k stay bonus.
I can only speak for the Marriott that we stayed at that the lounge offerings slowly got smaller over the year to the point that my coworker complained to the staff. Still adequate but used to be better.
Stayed at the Westin Tokyo last year and wasn't given an upgrade even though I tried to use my SNA but overall was a good hotel. Lounge was decent and so was breakfast offered in the other two restaurants.
I'll be staying at the Hilton Tokyo this year and that'll help me decide which chain I want to stay at more.