I specifically remember them announcing quarterly profits from YouTube in alphabets breakdown a few years back, they are almost definitely profitable, I'm okay with being proven otherwise but as far as I know YouTube is profitable now.
Maybe they're greedy, maybe more are using adblockers, maybe companies aren't willing to spend as much per ad due to the economy, maybe they are profitable but the margin is too low to be worth the effort and risk associated with running a platform. We probably won't know.
If we’re talking about Econ 101 maybe Google shouldn’t have purchased a company that couldn’t turn a profit after nearly a decade without rent-seeking.
But I'm sure a random guy on Lemmy knows a bit more than one of the largest corporations on the planet. You should apply for a job there, they might like your ideas.