Being worried about where you build things in this day and age is kind of unnecessary. Say hive suddenly decides to implode and price tanks to 0, the database is still there, SL could just take everything they have here and copy it over to another chain without the issues that made Hive implode.
The question is do you want to start building things here compared to other places and for that I'm sure we all know the reasons why you would want to as many projects have already seen a big success thanks to the large community connected directly to any project without the complications and fees, etc hindering them. Many choose to build on the giants these days cause they're after the money and most of the projects end up going nowhere mid to long term because it's like finding a needle in a haystack on top of the creators not caring cause they get their funding from gamblers who've profited from the layer 1 currency but can't get enough.
Yep. Or if all other witnesses drop out, they just fire up some more nodes.
There is so much value and security in building on top of an established community, yet like you said - chasing the quick gains means most will fail. They might make a bundle, but it is pretty much a more complex pump and dump project.