I'm not sure what you're getting at here. Are you complaining that 5e doesn't allow the DM to control which PC gets which item by choosing to hand out items for particular body slots? I mean, good? What business is it of the DM's who gets what item? And should it be important, why not use the other tools available like requiring attunement by a ________?
And overall, the magic item creation rules in 3e were bad. Mostly because items that didn't provide straight bonuses but instead mimicked spells, or otherwise had interesting effects, were vastly overcosted because of the formulas that were based on spell level x caster level (meaning spell level squared, because the minimum caster level was based on spell level), and because offensive items had DCs based on the minimum needed to cast the spell in question. I mean, who the heck
would want a DC 11, d4 damage wand of burning hands?
In my experience, it was common in 3e to get rid of items that didn't match what anyone in the party needed. You found a cloak of charisma +2 with no sorcerer or paladin in the party? Sell it. In 5e, there is no default magic item market. There are downtime rules you can use to try to sell or possibly buy things, but they're more akin to high-end art deals than going to the local Cannith enclave.