Even ignoring potential design impacts from transitioning from sealed batteries to ones padded with safety features to avoid harm to someone armed with a conductive screwdriver, I have to imagine there will be quite a few people who do not restore the device to its ip 68 rating.
So you risk people stockpiling batteries in case they need them later, and people who after repair increase the risk of them turning their phone into a pile of e-waste because they thought they could still get it wet. People also won't necessarily know the proper way to dispose of the old battery.
This compared to just having rules about needing to supply batteries which are replaceable by any appropriate state-licensed technician at cost for X number of years, and mandating the old batteries be properly recycled by said technicians.
(Thought Apple's $99 to do the repair themselves isn't terribly bad all things considered; and likely part of their attempt to forestall complaints and litigations).
Part of the new requirement should be they can't kill battery lifespan in 2-year old phones through software updates, either.
Because even "replaceable battery" doesn't fix that serious problem!
45 EUR for a new battery
10 EUR for new display adhesive
20 EUR for screwdrivers and a spudger (unless you have them already)
a suction cup and tweezers you probably have at home already
Ignore the 25 EUR clamp and 20 EUR heat pack, I did and they weren't needed at all. So all in all, around 910 USD less than you claimed.
The heat gun discussion in the sibling comments is also completely ridiculous. There must be 100 ways to do it without a heat gun. Put it on the radiator, use a heat pack for muscle soreness, or just borrow a hairdryer.
If somebody's unable to replace their iphone battery because they can't come up with a source of heat, I doubt they'd even be able to replace the batteries in their TV remote.
Myself, I've had bad luck with getting things sealed up just-so in my own phone-repair adventures (which can be validated well-enough in Samsung world by looking at the barometer's reading, squeezing the phone to create some internal pressure, and then watching the rate of change).
I like to think that I have reasonably-decent mechanical inclination, but the luck here has been bad anyway. I really just want to be able to take the battery out, put a new one in, and have it otherwise work exactly like it did an hour ago. Alas.