> Everyone moving to USB-C was the same standard, though; now you can use the same charger with your phone, laptop, tablet, other random gadgets, etc.

You could already use the same charger with nearly everything. It was the cables that were not necessarily USB on the device end.

Apple for example as far as I can tell has used USB chargers for everything (phones, tablets, music players, headphones, Apple TV remote) except laptops since sometime in 2012. For laptops everything introduced after the last MagSafe 2 laptop in mid 2017 has used a USB charger.

> if you can't find a replacement battery for that exact model.

Usually there are compatible ones that still give you some juice for 1-2 years at a small fraction of the price (of the original one).

If you worry about that, you can always buy an "official" battery in advance to be used 4-5 years later.

I believe part of the legislation is that manufacturers must make spare parts available for five years.