HTC and Motorola say they don’t slow old phones like Apple does

No need for artificial slow downs when you have Google play services. That thing requires more resources with every release.

Jokes aside, I don't think any other than apple does this. For one, android batteries are often larger giving them a bigger headroom.

On the other hand, maybe this is exactly what LG should have done to fix the bootloop issue (which seems to be due to a combination of bad soldering and excessive current draw during boot).

Of course, if you don't update old phones, how would you make them slower?

Most modern phones have functionality similar to what Apple implemented to limit current draw under low battery conditions to prevent brownouts. On Qualcomm devices, this feature is called Battery Curtent Limiting (BCL) and is used on their big.LITTLE based platforms. It disables the big cluster to acoid brownouts when the battery voltage is low. Motorola and HTC phones do use BCL.

"We don't slow down old phones. They just slow down by their selves."