Boy they are really lowering the bar what it takes to get in...
I thought it was the FIBA HoF until I read your comment. In terms of pure talent you are right, Radja would not have entered if he were American. Still, it's nice to get some variety in terms of nationalities.
There are more deserving Croats (Kukoč easily), let alone Europeans to enter this HOF. But his career must be evaluated as a whole, not just 4 NBA injury related seasons. 2 Olympic silvers (88, 92) World bronze (94), 2 Euro golds (89,91) 3 bronze (87, 93, 95), 2 Euro club titles (89, MVP 90), U-18 WC gold, also his salary was paid more than Maradona or Jordan at the time (91, 92)
I don't respect HOF choices as much, but he undoubtedly had an extremely productive career.