Good on you.

I agree that feelings aren't a valid argument, but that doesn't mean that we should just ignore them. If one chooses to act in a hostile manner that seems almost designed to piss off the other side of the debate, then one can hardly be surprised when the quality of the debate nosedives. If I had approached our debate here by yelling abuse at you, would we still be having this discussion, or would you have been too annoyed with my rudeness to continue debating dispassionately?

Ultimately, it all comes down to why one enters into a debate in the first place. If it's to get one's opponents to concede defeat, then that's less likely to happen if one's opponents are in such a fit of rage that they can no longer calmly self-criticise. If it's in the hope that one's own beliefs will be defeated and replaced with beliefs that are a little closer to the truth, then that's also hardly likely to happen when one's opponents are so angry that they stop arguing their beliefs logically (or potentially stop arguing them at all). If it's just to get the last word, well, that can be achieved by just shitposting until the other side gets bored of replying, but that seems a rather pointless endeavour, doesn't it?

Of course, we shouldn't refuse to argue our beliefs if they're potentially contentious and offensive, but we can still argue our beliefs while being mindful of the impact that both our beliefs and our tone will have on people. If I were to try to argue against gun control with a person whose relative had just been shot, I'd have to take great care to avoid seeming callous or disrespectful. In this instance we can see that the person's emotional state would make them unlikely to see reason (without a lot of coddling to dissipate emotions), but the same applies in just about every debate to a lesser extent: if I'm disrespectful to people I debate with, or to their beliefs, then they're likelier to just shut me out than continue with a decent debate.

So I posit that emotions aren't a valid stance or justification for beliefs, but they still can't be ignored in a debate.