Without taking risks, there is no gain. Wash trading=artificial activity, artificial volume. Volume has nothing to do with gains, but yes, it can simulate liquidity, popularity.
I have no idea if "SE tokens are a good investment". (Although, I invested a lot of money in them.) I'm only saying that the illiquid market can be better with honest market making activity. The cure for poor liquidity is more buying, and not more staking.
Nobody buys your token, but the market maker does. Nobody sells you the token, but fortunately, market maker does. And this person is risking his money and making a profit. What is wrong about it?
Staking is good. But with a liquid market, means, better exit possibilities, there will be more people willing to stake. I hope.
Nobody wants to invest in products which can't be sold at a reasonable price.