There is an extreme amount of difference in security between e.g. the axotlotl prototocol and only transport encrypting to and from the server. The benefits of OTP might become real decades in the future if we develop large quantum computers (or if we become a Kardashev type 2 civilization and suddenly can afford spending the energy required to boil all oceans on earth multiple times over to crack encrypted content by brute force).

Oh, the benefits of OTP are huge right now. Just to mention two:

1. the implementation can be trivial and so there isn't really an algorithm that can be broken or a backdoor in a RNG on your device.

2. Protection against MITM attacks (or anything related to problems with certificates, even bugs in your software)

That's an extreme amount of difference in security compared e.g. the axotlotl protocol.

Now, the authors of Signal are smart guys and of course they used the axotlotl protocol for obvious reasons, namely to increase usability. But you can say exactly the same about telegram too. It only becomes a matter of where you draw the line.

> 2. Only if you give it access, so also not obvious

Or rather invalid, unless you make it valid, and then obvious.