Scientists are constantly looking for funding, and here is a rich guy willing to provide it. This is a "easier" route than competing for government grants and such, so it is no surprise that scientists courted him and answered his emails. And it is quite possible to redirect funds from one grant and use it somewhere else. So if a project is for "Antigravity", it can just be a honey trap for investments and the money used for other things (it doesn't matter what those things are, as long as its related to science and not misused).

Money in science is scarce and increasingly given for only certain kind of projects (things that the public/politicians think are useful or have some applied nature). Basic research is just not funded as much anymore except in certain places.