I wonder how profitable the ads are, given how aggressively they try to push me to signing up for their subscription (also, they seem to increase the number and length of the unskippable ads when they promote their subscription).

I ended up installing Newpipe instead, which is a much better experience.

Seeing how everyone installed Chrome by being pushed the same way, there are probably a lot of people that sign up for this service... so they probably also make a good chunk there.

They don't appear to bug me much though... maybe ublock origin blocks those ads.

On desktop, yes. But on mobile you either have to accept the ads or use Newpipe.