I played Basic D&D when I was 10 years old and I play Basic (B/X and OSR retro clone equivalents) now as a 40+ year old.
There is an enormous difference when we played as kids to how I play it now. Now, revisiting the rules as an adult and playing them as intended creates a much different experience than the more kick down the door way we played as kids... although to be fair, that was a long time ago, but I mostly just remember fighting monsters.
I know it is just anecdotal, but myself, as an adult playing old school games, I just have never seen the arbitrary deadliness that so many people claim occurs in old school D&D.
I recently ran a weekly OSR Meetup game. We played Basic Fantasy RPG by the book in a megadungeon.
Basic Fantasy is an retro-clone based off B/X (1981 edition Basic set). It has a slightly different attack progression and thief skill table and some differences in spell descriptions, but it is for all intents and purposes equivalent to B/X (certainly in terms of deadliness).
In about a year and a half of weekly play, I had a total of about 24 players join in and play. Some were regulars, some came and went, some popped in once and a while. I had between 6 to 8 players every night. We started at 1st level max hit points. Some players had henchmen, most did not, though.
The regular players started hitting 3rd and 4th level after about 10 months of playing.
I had about a half dozen or so character deaths and about the same number of henchmen deaths. I had little Death Certificates that I had players fill out when their character died. When a player's character dies, they roll up a new 1st level character and join in as soon as they are done.
I used standard B/X style dungeon exploration rules... including wandering monsters, resting after 5 turns, reactions, and morale. The players tended to be cautious but threw down when needed.
Of the six or so character deaths, pretty much
the majority were due to a poor player choice or decision. Some of the deaths that I remember:
- Player had their character run into a crypt and close the door behind him (before checking contents) Eaten by the zombies that resided within the crypt.
- Player ran away from a monster, in the dark, through an unexplored passageway... fell into a spiked pit trap and died.
- Player asked their henchman barbarian with a great axe (his PC was a thief), to swing at the Stirge attached to him. Henchman missed the Stirge but hit the PC killing it instantly.
- Fighting against giant scorpians. The 1st level dwarf stayed in the back and used crossbow. Then decided to charge to the front line. The mighty dwarf killed one scorpian but the second stung him and he failed the poison save and died instantly.
- Player charged head first against ghouls and got paralyzed and eaten.
Pretty much most deaths were due to a poor move. In all, I'd say the game was not at all deadly. Certainly not to the level that many people say. Players who were smart made good choices were able to have their characters survive.
Old school D&D doesn't necessarily have to be the arbitrary death fests that many people claim it to be.