Ignoring the lack of updates if the game is buggy, games back then were also more focused on quality and make gamers replay the game with unlockable features based on skills, not money. I can't count the number of times I played Metal Gear Solid games over and over to unlock new features playing the hardest difficulty and with handicap features, and also to find Easter eggs. Speaking of Easter eggs, you'd lose a number of hours exploring every nook and cranny finding them!
Comparing modern game with games from the olden days is a little bit like comparing a savery steam pump with a modern internal combustion engine. Sure the general principles are identical but the complexity of the system is a manifold of the other.
I really love retro games, i have very fond memories of the C64 and SNES, but i am not a fan of the glorification of those games. Only a small part of the old games are still fun today and lots of them have bugs. Secret of Mana on the SNES for example has a fun bug where leveling all weapons and spells to max can create a overflow error in the final fight of the game, which removes the mana hero completely from the game, rendering the last fight impossible because only the mana hero can damage the mana dragon significantly.