To hold BTC you don't need any bullshit trust.
You just hold your own keys, wherever you are. Are just 12 fucking words, damn it.

Here is a simple example of you hold secret keys to your BTC.

Read more:
https://darth-coin.github.io/beginner/be-your-own-bank-en.html

hold shares in other companies

That is shitcoining, bullshit crap. Only Bitcoin matters.