The HP creep has been across all editions of D&D and AD&D. In OD&D, fighting-men got d8 hit dice, same in "basic" D&D and AD&D 1e. In AD&D 2e, Warriors got d10 hit dice. In D&D 3e/3.5e fighters got d12 hit dice. In D&D 4e, they got 12 HP per level.

Weapons saw a similar power creep with the hardest hitting weapon in basic D&D doing 1d10 damage, in AD&D 2e it's 2d6 damage. In newer editions, weapons can go higher, sometimes much higher.

In AD&D 1e, the creature with the most hit points (In Deities and Demigods) had 400 HP. In D&D 4e, it was 1500 HP (Bahamut iirc).

There's also the difference in maximum level. Basic D&D had a max level of 36. AD&D 1e and 2e had a soft limit of 20 levels (though it was possible to keep going and one adventure was even published for level 100). D&D 3e had a limit of 20 levels unless you used the Epic Level Handbook, which extended it to 40 levels. D&D 4e had 30 levels. D&D 5e has dialed the level limit back down to 20 levels.

All that aside, there's also magic resistance in AD&D. Sure, in AD&D you could smack Asmodeus with a 20d6 fireball, but he had 95% magic resistance (so on a 94 or lower on d00, the spell failed). and even if you got past that, he was immune to fire, but assume you somehow negated that (dunno how, maybe with wish?), he was also immune to spells of lower than 5th level. He only needed 200 HP because your mage was 95% useless at that level. You also better have a good sword because most stuff is immune to non-magical weapons at high level.

You really can't compare game math across editions. It doesn't translate neatly. It's even less neat when trying to translate between the "classic" systems from TSR which were largely compatible and used similar math and the "modern" systems of WotC. They may as well be totally different games from a mechanical perspective.