>>96770652
Shadowdark has Gold as XP, while 1e does not strictly have just Gold as XP. Calling it central to the core of OSR might backfire for you.

More importantly, in general play, Gold as XP is functionally interchangeable with many other systems, with the practical differences being nuanced at best. If the goal of XP in general is to encourage players to go into the dungeons and explore, XP for Tiles/Rooms explored does a very similar job. XP for killing/outwitting/pranking Monsters (something 1e includes) also does that while making random encounters a bit more rewarding than pure Gold as XP where gold is not always guaranteed. Even something dreadful like XP for "milestones" can be incredibly similar to XP for treasure, with the huge piles of gold that pushes players to the next level replaced with purely arbitrary "you reached this point, congrats" kudos. There's plenty of nuances that alter the experience in different ways between these options, but trying them out and seeing how some can improve (or worsen) the game is also a part of OSR and RPGs in general.

Hauling gold back is not really a vital part of OSR, and includes a lot of unpopular aspects like backtracking and having to devote attention to tracking encumbrance considerably more. If the goal is to encourage players to complete the Town/Dungeon/Town loop more often, there's lots of other options beyond just "you're carrying too much gold", and even just retaining "You need to train outside of the dungeon in order to turn XP into levels" does a fair chunk of that.

Also, the "OSR playstyle" is not a singular playstyle and never was, making your entire statement about something being central to driving it wholly ridiculous.