I think that’s probably right, although this particular episode is actually generating a lot of backlash amongst viewers (check out the show’s Reddit to get a sense of this).
Many seem to feel like this was a frivolous showcasing of sexual assault - definitely quite a controversial episode!
I've seen people mention this a few times and I've been thinking about it on a couple different levels. For one (and most relevant to this discussion space) something interesting to point out is that this scene was one of the (if only) instances in mainstream media depicting one fictional character utilizing tickle torture on another character for the explicit purpose of sexual arousal/gratification. Every other instance I can think of is either a character being tickle tortured for information or to inflict discomfort/humiliation. Even tickling scenes between couples have tickling as a "cute" interaction that progresses to kissing (or more) but the act itself is never really made out to be inherently sexualized/sexual.
The only other instances that come close that I can think of are the documentary Tickled which I don't think counts because that messed up situation actually happened irl. Also iirc there was a storyline in CW's Riverdale regarding male character(s) getting filmed for tickle fetish material but from what I'd read about it there wasn't a character watching said tickling on-screen and becoming aroused from it. This contrasted with the scene from The Boys where Ashley is literally rubbing herself off and cumming from the act of Hughie laughing and begging while she's tickling his feet with a feather. I'll join the chorus of comments saying I'd have much preferred Starlight, Kimiko, Ashley herself, or Firecracker being on the receiving end of a foot tickling sequence but in the context of the show and what it's adapting (I'll get to that in my next point) I get it.
The scene/episode itself was actually adapting and mixing a couple different moments/stories from Garth Ennis' original comic story. The first is the idea of Hughie disguising himself as a superhero in costume to infiltrate a gathering of some sort. The second is Hughie being the victim of sexual assault. In the comic version of The Boys this occurred very differently with
spoilers for anyone interested in reading the comic series The Boys
Black Noir (who in this version is a deranged clone of Homelander) ambushing an uncostumed Hughie alone in an ally and anally raping him while repetitively whispering "Good soldier" during the act (a specific reference to Batman who Noir was an unsubtle pastiche of)
End of Spoilers
So with this in mind it actually makes a lot of sense that Hughie was on the receiving end of the tickle torture. It's also interesting in that the showrunners/producers very intentionally went a very different way with the who/how of Hughie experiencing sexual assault but still had it occur and also had Hughie visibly traumatized later on in the episode as a result of the situation. This compounded with the trauma of what had happened to his father only an episode when the entire tickling/BDSM sex dungeon could have otherwise been played off as a less serious and comedic moment solely played up for the blasé shock value the series has become notorious for.
I can understand why people online could have the criticism of the scene and specifically the sexual assault being frivolous but considering the context of the scene with Hughie and Annie afterwards I'd argue that the writers if anything did make a point to spotlight the sexual degradation and resulting turmoil experienced by someone involuntarily participating in a tickling fetish scenario in a (imo) genuine and realistic way. Especially considering context of being on this very site and having our specific fetish when stories, clips, art in line with this type of involuntary scenario more often than not sexualize and even at times romanticize it.