I Honestly think it's not about rooting for the ml or 2nd, it's more like, at least to me, a good story and yes you're right about been here not because of the romance, get ruined because the author decided to add romance and the worst part to someone you don't find desirable to be with the mc.
I do rather if the story didn't have any romance, it already great, the dynamics are top notch. The romance will just stress me out.

I find it funny how ppl are rooting for the obvious 2ML but if he was actually the ML we wouldn't even have an interesting story, nobody would even read this if he was actually the ML and don't you dare lie and say you'd read it we all know you wouldn't lol and this is tagged as romance but tbh the romance isn't what's keeping me here so it's funny to see how ppl are so romance focused.