The normalisation of words like ‘stupid’ does have real life consequences to people with learning disabilities. Any time you use that word or similar words, you are not only insulting the person it’s directed at, but you’re also insulting all people with a learning disability by insinuating that they are in some way inferior, because according to you their disability is an insult in and of itself. You will not gain any sympathy from the disabled community by normalising those words. You’re pushing them away and throwing them under the bus to be targeted first.
‘Weird’ is not an equivalent word because it doesn’t define a group of people in the same way. Walz’s usage of the word ‘weird’ wasn’t to insult transphobes. It was a correct assessment that republicans are way too interested in controlling the personal lives of trans people in a way that most people would (and should) be weirded out by. It’s weird (and creepy) to find a stranger in your bedroom in the same way that it’s weird (and creepy) to have a stranger tell you how you should dress, behave and look. It’s an argument that has substance, compared to the empty argument of saying that a transphobe person is of ‘low intelligence’, especially when that’s often not even the source of their transphobia.
Substantive arguments are always better than non substantive ‘mean’ arguments as you call them. You’re not arguing to convince a nazi, you’re arguing to convince a bystander that a nazi is dangerous. A bystander needs an actual reason to be convinced, not a few mean words.
You claim a lot about antifascist strategy but your claims are not supported by historical evidence. The strongest antifascist factions have always been those that seek unity within oppressed groups. Tailism just leads to division.
All your arguments are based on claims that are guesses or just plainly untrue. This not not a serious discussion. It makes sense that your sources and ‘experiences’ come from vaush and twitter. Touch grass, talk to some experienced antifascist activists and maybe read some books.
Edit: and maybe reach out to a disabled community (in a respectful manner) to learn about how ableist language impacts them.