Thankfully, I have a lot of praise for this puzzle! Otherwise, I might have come across as a bum. Worse yet, an ass.

A few years ago, I had a fun conversation with Will Shortz about butts and lewdness. Back then, he could only allow the word ASS in the "boor" sense, the NYT frowning upon the "keister" meaning. It seemed like a strange stance, given Will's liberal use of "moon" clues for words like REAR and TROU.
This has eased over the years, giving Will the ability to run a puzzle like today's, which forms BOTTOM ROWs composed of no ifs or ands, but a whole lotta BUTTS. I've seen much BUTTplay in the crossworld — maybe that's not the best wording — but nothing quite like this. I'm impressed by the sheer quantity of theme words defined in non-patoot ways.
I would have liked a different revealer, though. BOTTOM ROW does define the concept perfectly for crossworld insiders, since we all talk in rows and columns. I'm not sure that applies to the general solver, though. BOTTOM LINE seems like a more familiar, more accessible term.
Placing the BOTTOM revealer in the middle felt odd, too. Why not at its natural position ... toward the bottom of the puzzle? I can imagine using BOTTOM LINE in the same row as FANNY, to form a final "bottom line."
What, you say that that wouldn't technically be a line of only bottoms, since it would contain the word "line"? Sheesh, why do you have to be so anal?
As much as the juvenile in me likes seeing the multitude of butts, something less audacious would have been better. BOTTOM ROW in the middle causes all sorts of gridding problems, especially when you need four extra rows of themers. Newbs encountering APSE ETTE OLA right off the bat might not stick around to get the beautiful SKI CLUB, HAND DYE, TANDOORI, as well as Amy POEHLER's "Parks and Recreation" COVID-19 reunion.
That's it for me; I'll take a seat now. By the back door, of course.