Lanefan
Victoria Rules
Well, until the party ate a fireball or lightning bolt and failed their saves; on which that hundred magic items might fairly quickly become fifty rather charred magic items and a bunch of slag.5E gives a gp value range for rarity. The Downtime rules in Xanathar's uses those values for buying magic items. It's not like there's no GP values in 5e magic items.
And, I would argue that 1e absolutely did have wealth by level. But, it was largely opaque. You were expected to be absolutely dripping in magic items at fairly low levels, compared to later editions. The paladin being limited to a mere 10 magic items was meant to be a heavy restriction. In a group of 6-8 PC's, you were expected to have close to a hundred magic items, fairly quickly.

I've seen these cascading meltdowns before. They're like train wrecks - you don't want to watch but you can't look away.

Sure. And you may or may not be able to use half of them due to alignment, class, and-or proficiency restrictions.And the modules certainly supported this as did the random treasure generation tables where you could easily get 4-6 magic items from a single lair.
Like I said before, you had to go pretty nuts before hitting "Monty Haul" status.But, as @pemerton rightly points out, the whole "Monte Haul" thing in the DMG and many, many sources throughout 1e and 2e meant that the system absolutely DID care if the party was overpowered.