(disclosure: i work on gcp)
i asked this question to one of the people in my orientation and he said that if you don't believe what they say, one real thing they're doing is hiring bunches of new people to work on gcp. also, gcp runs on the same underlying infrastructure as the rest of google, so were i to guess just keeping it running would be relatively cheap.
What I witnessed was a feast and famine cycle. Senior leaders were always ravenous for headcount. In good times they would get it, and allocate it to increasingly dubious ideas. In bad times they would be forced to lay off even more than they had hired. Everyone from the dubious ideas, plus some of the maintainers of business-critical stuff, would be let go. The remaining engineers would (rightly) complain that they were understaffed and bereft of vital institutional knowledge. As times got better the gaps would be backfilled. But the company never had the restraint to stop there, it would just go right back into the cycle.
Add to that a not-invented-here / not-invented-by-me problem. A platform with some warts probably could have been fixed by those who understood it. But those people were gone. So the team genuinely needed larger headcount than before the layoffs, in order to rewrite the thing.
If I had to root-cuase it, it's that senior leaders get no points for delivering outsized results with a small contingent of engineers; their prestige and leveling is all about the headcount growth occurring beneath them. So there's no pushback on headcount growth, until there is.
If a company is going to go bust in 6-12 months and the metrics wouldn't warant further investment. Then the senior leadership may opt to increase the burn rate to run out of money in 3-6 months with the hope that the extra headcount will solve the deathly problems coming up at the end of the year.
At the very least it can help drum up interest from investors based on "look at the new X we shipped, or look at how strong our team is"
Hiring in the US may be a big expense, but it's not a commitment to much beyond the WARN Act requirements.
Of course, there's the issue that when a company has lost the trust of internet cynics, there's not much that company could say to convince them of a commitment. maybe a public, long term contract with some organization of consequence... but you can always get out of those by paying fines or malicious compliance.
We're moving our software to the cloud, and the people in power had dismissed Google before discussions about which provider to go with even began, simply due to their reputation for killing off their products with short notice.
Probably a bit reactionary, but I'm not going to stick my neck out for Google on that one.
I heard that they're moving some of their core products onto GCP, like parts of YT. If this trends keep going up over the next 2~3 years, maybe you don't have to worry too much about GCP itself, though there still might be smaller deprecations.
While I personally believe the fears of GCP being deprecated are overblown, the reason you give isn't actually true. Internally, Google is all for deprecating products with a ton of usage if it's inconvenient to maintain. That's why all internal tools got a new UI in the last year or two, because they deprecated the UI framework while everyone still depended on it.
Most of the deprecated Google products have either alternatives or generate no direct revenues. GWT is just a library in the second category, replaceable with a few hundred SWE years. Unlike that, GCP and YT are making real revenues in the order of billions. This is what "core product" means.