Every RPG has to have like at least 20 levels today, it seems. Back then that was only the norm in loot&level action hack&slash fests like Diablo, completely hinging on that kind of gameplay loop. Nowadays even in games such as POE Deadfire you've barely shipped past Tutorial Island, and have already leveled up a fistful of times in the process (for the record, in BG3 you also level up comparably fast early on, which adds to the problem perceived by the OP).
I think if the Realms Of Arkania trilogy were to be released today, people would rage all over the place. Each entry is a full game -- and each covering 2-4 levels at best. By the end of the trilogy, you're usually level 8-9ish or thereabouts.
Mind you, the DSA P&P system behind that at that time was in many ways opposed to what devs&players consider addictive video game progression: Not only are all/most spells available right from the start -- it's also only a matter of how reliably you can cast them (which gets better over time provided you level them up). Additionally, in the game, you can get and access the best gear immediately from the shops, provided you have the money... no magic fat loot everywhere, you got your gear and then for many many many hours things would change zero.
Ah, that would be fun to see those released into today's markets. PS: Larian's very first RPG prior to the first Divinity also was a game based on the same ruleset and setting. They worked with the same publisher too (but it went bust). Young Swen can still be seen here:
PS: Larian's very first RPG prior to the first Divinity also was a game based on the same ruleset and setting. They worked with the same publisher too (but it went bust). Young Swen can still be seen here: 