he kept coming up increasingly weirder and mundane reasons why we should blame desiigner.

What's weird about saying he should've tried to adapt?

You can't use one example of a much more versatile and creative artist in tech9 and think that applies to every rapper!

There's nothing about Tech that Desiigner's incapable of. We're all just guys, some of us try harder than others. That said he's very not the only example. Look at people like Krizz Kaliko who can eat your face off in a cypher and then turn around and sing like an angel live.

Being able to adapt is absolutely everything in this genre given that rap is nothing by itself without pulling from every other genre around it. All rap is by itself is poetry with rhythm, so the more styles you're capable of the more likely you are to avoid finding yourself in the situation Desiigner did here.

you cannot blame an act for playing as he always does.

You very can. If I hire Slash to perform at my wedding I expect him to play a wedding song as opposed to busting a crazy fast finger-breaking metal riff. If I hire Louis CK to perform at my daughters birthday I expect him to avoid talking about shit going up his daughters pussy when she poops in her diaper. There's an expectation when you hire huge acts that they're capable of adapting said act to whatever audience, otherwise they wouldn't be that big in the first place given you assume nobody wants to put themselves in the position Desiigner did here.

it was desiigners fault that these people didn't like his performance?

It was.