Why do right wingers insist that covid came from a lab when the evidence points torwards it coming from the wild?

They never met a conspiracy theory they didn’t like?

In politics stupidity is not a handicap- Napoleon Bonaparte

The same reason that Russian state media insists that the colonies were developing anti-russian bioweapons in secret bio labs in Ukraine.
The same reason that the Nazis accused Jews of starting wars and controlling the banking industry.

If you accuse the enemy of something nefarious, and your rube followers swallow it without question, then you have a justification for any violent or repressive action you intend to take against them.

It’s not all right wingers, you have plenty on the left that believe it too. There was just enough circumstantial evidence to convince many the lab leaked it. It’s possible that it did too. The data used to triangulate the source mostly came from China so many don’t trust it. You also have the Alex Jones conspiracy nuts going crazy stirring up that leak idea.
Despite all this, I can’t say that I’m 100% convinced it did not leak from the lab. You just can’t convince me it was part of some sinister plot though.

Probably because that’s what the news said back then.

Politics. Anything to discredit the other party. It doesn’t need to factual – just negative.