Isn't it also easier to license ARM, because that's the whole point of the ARM Corporation.

It's not like Intel or AMD are known for letting other customize their existing chip designs.

Apple was a very early investor in ARM and is one of the few with a perpetual license of ARM tech

Intel and AMD both sell quite a lot of customized chips, at least in the server space. As one example, any EC2 R7i or R7a instance you have are not running on a Sapphire Rapids or EPYC processor that you could buy, but instead one customized for AWS. I would presume that other cloud providers have similar deals worked out.