1. So a lot of martial classes don't get an equivalent attack score until level 8. Which is pretty far into the game.
2. The "significant" cost being referenced is not significant. It doesn't touch the fortune my party has amassed, at any rate. And that's only talking about the ones that have to be purchased, as opposed to found or stolen.
3. I don't particularly care about what items were or weren't invented for the game.
4. It's the abundance of the items coupled with the way they last until a long rest. In other words, all the time.
5. The dex based fighter/ranger/monk/whatever doesn't even have to bother using their main stat for 8 levels of a 12 level game.
6. The pact of the blade warlock is using strength instead of charisma in melee for the first 8 levels of the game.
7. The headband of intellect is not the same. It takes a head slot which is a very valuable resource that could be used otherwise. It also happens to get the score *equal* to what a starting character could get, and can be surpassed in the first 4 levels. It's not even close to a valid comparison. (The opportunity cost of an elixer is nowhere near the same.)
8. It's just a bad design. Whether that bad design stems from Larian or DnD is irrelevant, in my opinion.