Iām not really sure how controversial this will be, but I canāt see Senku as anything other than romance indifferent/repulsed (THIS IS MY OPINION ALERT THIS IS MY OPINION.)
I am ABSOLUTELY certain that (at least in the main manga/anime) he at least isnāt into women (whether intentional or not on the creatorsā parts)
I would get the āSenku does find women attractive heās just busy with other thingsā argument more persuasive if he seemed to be only indifferent to the advances, but look at him
Heās looking downright uncomfortable, even slightly disgusted at the thought of romance.
Though he states that his reasoning is that relationships are illogical he also clearly recognizes that heterosexual relationships will be necessary for civilization to continue, and though he seems slightly annoyed when his friends get too mushy with their crushes, heās usually fine with it (even supportive in taiyuzuās case).
Even in places where romance/relationships are the practical option, like with Luna, his first reaction when she asks him out is screaming and making this face:
Before his rational side prevails and he agrees likening it to a political marriage of convenience, where he proceeds to avoid doing anything romantic with her. (You could chalk that up to him being shocked at her bringing that stuff up at that moment, but idk I feel like heās kept his cool through WAY weirder shit)
When he has to pretend to be Kohakuās boyfriend to fool their enemy, he doesnāt even TRY to make it convincing even though if they donāt fool Kirisame it could be the death of them.
I canāt prove he isnāt into men other than my personal belief that his distaste when he talks about romantic relationships is talking about romance in general, not just with women.