They grew their employee count massively (400->2000) as their revenue grew over the past few years though. Part of that is, yeah, you have to spend money to make money. But I know for a fact not all of those employees were doing ad sales or direct monetization.

You can speculate as to why they hired so many people: pandemic tech hiring FOMO, looking more attractive to investors, empire building, not being willing to settle for a paltry 10-figure valuation and so trying to build out to hit 11-figures. But they don't need that many people and they could easily become profitable by doing a big layoff (just as money software companies could). At this point it's not a question of survival or existence for them, nor of IPO readiness, so much as it is IPO optimization.