Mozilla might be the best out of this, but they're also in the weaker position. Ads, whether they respect privacy or not, give off a scummy feel to users. The clean Chrome UI, even if it tracks you in a hundred ways, "looks" more trustworthy to users than a browser riddled with ads.

It's bad enough to have to instruct people how to disable the New Tab ads, now you have to add one more step. At this point it becomes pretty awkward:

"Don't use Chrome browsers, they don't respect your privacy and are bad for the web! Use Firefox instead. Oh but wait you have to disable integrated ads first, just do this and that and this and I swear it's fine!"

Chrome apparently already has similar suggestions in the address bar.

You're not wrong.

This is why I use Ungoogled Chromium and build it myself.

Well that's more effort than just disabling the New Tab ads on Firefox and you're clearly technically inclined so this doesn't go towards my argument.