To be clear, there are no legal reasons I can think of that would ever prevent internal use of LGPL/GPL software.

You mean these companies (Apple, for example) have policies.

Policies like this often change because someone decides the cost vs risk tradeoff is worth it.

Changing a license because of bad policies of certain companies is not a great reason to change a license (in fact, it's, IMHO, an actively bad one).

You really should only change licenses if you find the license you chose does not suit the needs of your users (and policies are not really needs).