I mean, if they were questioning their sexuality, then obviously they’re not sure. So your question was redundant and out of place to say the least.

Also, as already said in this thread, people don’t generally challenge heterosexuals regarding their actual experiences. So challenging a bisexual/homosexual person about how they feel regarding their sexuality based on their actual experience with other partners does indeed feel like an invalidation and therefore disrespectful.

And at last, on the internet, for many different reasons, it’s quite normal that a debate becomes hyperbolic. But dismissing the situation telling people they’re oversensitive and privileged because of your own lack of tact to deal with the situation doesn’t help your case either.