I used to feel the same way, but the interface is actually super customizable if you are ok with editing config files!

Here is the manual.

There is also a huge variety of third party scripts, like this one shows thumbnail previews when hovering over the seek bar.

Relevant Silicon Valley scene

Hopsan shares similarities with Simulink, and can also work together with it.

Signal is certainly not. It’s open source, and verifiably end-to-end encrypted. The only information that they have about you is your phone number, when your account was created, and when you last connected to the service.

Telegram is not so privacy friendly, with a major problem being that it’s not end-to-end encrypted by default.

For YouTube frontends: On the Linux desktop, there is FreeTube, on IOS there is yattee (IIRC), then there are web based front ends from invideous.

Louis Rossman mentioned the other day that they are in the process of creating an app that will allow you to follow your chosen creators across multiple services, so that you can continue even if their primary platform removes them.

If you’re looking for YouTube alternatives, check out Peertube, Odyssey, and Nebula (I haven’t looked at Peertube or Odyssey in a while, so I can’t comment on how they are doing).