Basically we don't know the risk in every site if you invest money in a site first is you don't know if the site was trusted there are site that can give you small profit but many site are just scamming people who invested.
Investing in bitcoin is also a risky investment where you could earn high or low income but if you have some skills in investing you could probably gain high income. I agree that you must know the sites first before you invest because there are many sites who are just scamming people. Lastly, even it is risky investment you must still invest because investing in bitcoin is one of the best way to gain high income.
I think your point about knowing the companies you are investing in before investing in them is the mot important thing ever. Think about it, how many companies are starting these days in the crypto world and we have no clue who they even are at all? Like, it is absolutely ridiculous and then they end up just closing and we lose all our investment because they sell their pump and dump and we lose everything!