It had been in the works for a while, but now it has formally been adopted. From the article:
The regulation provides that by 2027 portable batteries incorporated into appliances should be removable and replaceable by the end-user, leaving sufficient time for operators to adapt the design of their products to this requirement.
Aesthetics are the same bogeyman excuse used to justify really any significant change in a phone since IP ratings first came in with. I recall back when USB-C was first showing up in smartphones, there was a time where simultaneously some manufacturers were pushing for the change and others trying to push back on it, with both groups citing aesthetic reasons.
I want a laptop keyboard like ThinkPad T60, and usually the explanation why not is “aesthetics”. Because we don’t type on keyboards, we bloody look at them all day feeling fancy.
Yeah besides aesthetic preferences change over time and people just grow to prefer what’s ever modern. Or to tolerate it and then that becomes the standard. I don’t remember people bitching that phones were too thick back in the day. Obviously their primary motivation is planned obsolescence and increased phone sales.
It’s incredibly naive to assume there’s any other reason. I’m just absolutely no reason for them to stick glue on the battery or the serialize parts, other than to sell more phones and warranty plans.