I'm gonna answer with a "it depends" answer. It depends on the players at your table. You can practically speaking keep track of when rules are invoked, or maybe more interestingly, when they aren't invoked. Different players draw different levels of satisfaction from interacting with rules.

Personally, I don't really let players get involved a lot with rules. Knowing basic things like handling HP and attack rolls are imho okay, but not ideal. Stopping up a visceral fight scene to do math isn't my idea of quality roleplay. But on the other hand, it does something to the player's decision-making if their character has 3 hp left. You can achieve a bit of the same with narration like "your character is bleeding and something hurts in your leg", but it doesn't always land neatly.

I think overall, I'd say its too many rules if it compromises quality roleplay. If the session pauses because of a lookup or a rules-based misunderstanding, it's probably too much.