Whelp, even for tech-core products, number of engineers are often very insignificant compared to other stuff(legal, license, buying, acquisition, hr, advertising, marketing, sales, security, management, decision board, product management, product owners, agile team, release team, test/QA, support etc.).

I used to think that, tech companies could do with like what 200 people max, but after working on few places for a while now, I am no longer surprised, specially when your service spans the globe(or even multiple countries or continents), you really need a huge team to keep troubles out and the wheels going.