I don't have much problem with TPM Anakin. Of course they could get a better actor and make everything less childish. The main problem is Anakin in AOTC and ROTS, where he is just an annoying unlikeable jerk. I can't think of more a disgusting character in any other film I have seen.
Arguably the pre-ROTJ Force was such a merit based power. The reason we don't have Jedi is we don't have Jedi masters to school us in the Force. Even a farm boy on a planet in the middle of nowhere can become a Jedi.
In ROTJ the power of inheritance is introduced and Luke's sister is a Princess but she is an adopted Princess so she might be still 'low born'.
In the PT Luke and Leia are the offspring of royalty and a demi-God.We have gone from the age of Aquarius back to the age of Dragons. Luke is no longer Uri Geller with Kung-Fu moves, now he's a royal prince with magic blood.
Direct inheritance is a stupid concept, but the concept of anyone being able to become a Jedi if just willing to work hard is just as stupid.
The ability to interact with the force should be a rare random gift. An equivalent to rare gene mutation that makes some humans immune to some disease etc.