It is! Or at least honor the lounge access for booking made prior to Bonvoy as courtesy.

But anyway, it seems like Marriott effort of aligning the luxury brands elite benefit is by simply lowering down other brands benefit to match the ritz carlton offers.

Not the good way ... service/recognition wise to be honest.
Reaching titanium and ambassador level require quite significant spending and yet Marriott rewarding these members by not giving some of good benefit on their luxury brands.