I don’t know the games you linked, but all the games from nimblebit and from kairosoft are sim games where you put people to work and you have to wait for them to finish.
I’ve played Tiny Tower, Pocket Planes, disco zoo, and Dungeon Village 2.
None of them require an internet connection, some have ads which give you a boost, and some have paid tiers to remove the ads.
Sure, probably they won’t use it for bad purposes.
But there’s nothing saying they won’t use them in any way they see fit.
Maybe they could find a way to find monetize without disclosing them and anonymized, like statistics or with the update in their policy about training their models with whatever information they can get.
Maybe you have an ad blocker and AdSense can’t build a profile from you, but the google already know what sites you were interested enough to make an account and could try to advertise in other ways.
And then the biggest issue: there’s no mention of encryption, so who knows how they store them and where. Could an attacker read them? How are google employees prevented from reading them?
Send secure message takes you to matrix, which is a dedicated messaging project which has encryption.
Send message uses lemmy, which uses federation which is basically public (well I’m not exactly sure if the messages are public like the rest of the activity but the message is sent and saved in plain text, so at least the instance admins can read them)