"Just" ban fast-fashion and ban weakening the clothing on purpose (like tears and acid washes) Normally I would not call for bans, but that's Europe and they're into banning things, so that's my recommendation.
A Bonobos is fast-fashion, but a Gitman Bros less so; you'll see the same cloth/pattern/colors year in, year out. Maybe the collars change over time and maybe they'll add darts one year...
Uhmmm, so your answer is to have to some group of people asses every item of clothing or every new brand that pops up to see if it qualifies as fast-fashion based on whether it was influenced by recent catwalk trends or whether the factory it was produced in made it too fast or efficiently. ? yikes. Not sure if you realize that just how subjective and unscalable that is.
Breaking before those 2 years during normal usage is usually considered a flaw. In case of a dispute, it's on the seller to prove that the customer did something that's not considered normal use.
Once an item is fixed, the fix gets another fresh 2 years.
In principle I don't see why most clothing couldn't be covered by a similar scheme. It would force the producers to make clothing that actually lasts. Sure the price would go up, but you'd need less of it.
There's a shop here in Oslo which has moved in this direction[1]. Their stuff is made from durable fabrics and they allow one free repair.