Investment in formerly communist countries had the potential to be very rewarding. Many legitimate western investment firms were attracted by companies that carried a very low price tag, often a fraction of the value of their physical assets. Some of these investors got badly burned, usually by underestimating the depth of the corruption in these countries. Some of them lost everything, some of them were actually placed in physical danger.
See Bill Browder:
https://time.com/5340545/bill-browder-vladimir-putin-magnitsky-act-donald-trump/
And some of them played these complicated hand of cards just right and made money for their investors. Players in this game included not just small risk taking investment companies but large conglomerates like Exxon-Mobil.
It is worth noting that many of these investments were in the Russian/Ukraine energy sector. The USA, for a time, encouraged the nurturing of these companies as a route to lessen US dependence on Middle East oil.
And..Well before Trump oozed down the escalator at Trump Tower, people assume that Hunter Biden was doing something different than the things that dozens, if not hundreds, of other American investors were doing. Yes, investment in the international energy sector is a dangerous and often unsavory game but it is a game played by lots of people and encouraged by US policy.
It's funny though..Joe Biden runs for president..THEN all of a sudden what his son was doing overseas, in a very blakmailable country, is suddenly attacked and is front page news. I think we know why.