Why would publicly burning an advertiser on their channel cause other advertisers to be reluctant to work worth them?

Could be any reason.

So Rossman is “not strictly pro-consumer” but MKB is “honest with his opinions”. Up is down too, I guess.

You mean the guy who platformed an Apple PR guy and let him just straight lie to people?

Here’s an actual pro consumer youtuber talking about him with LOTS of cursing if you’re sensitive about that sort of thing.

They didn’t say anything because they’re not pro consumer, they’re pro linus media group. They didn’t want to appear to be unfriendly to advertisers. There’s a reason tech jesus was able to do a big expose on how crap their videos are. They want to churn out content and make money. Being seen as a problematic channel for advertisers doesn’t help that.