There are good ideas behind the videos.
There are some general mistakes in all three videos:
- Font weight and distance
- Status bar size and placement
- Notch and homebar size size on iOS mock-ups
- Wrong Premium badge color on all videos. It needs to be unicolor.

The rest are written per-video:

1. About the first one, it is not easily understandable what the purpose of the video is in the beginning. There is no short text inside video or any text outside, so it took me 3 loops to understand its purpose. The bars of "Messages" and "Global Messages" both have a "Show More" button without any back or cancel, but what happens if I tap on show messages of Messages and then I want to reach to Global messages? I bet it will go down forever.

2. I like your idea but there are some general problems here. Firstly, who is a friend? In Telegram, only contacts and mutual contacts are defined, but the definition of friends doesn't really exist. Secondly, inside the map, there are only other people's profile pictures. There are many people with just names and no PFPs, which will be problematic here.
Two more errors: the chatlist's last item is sent in a time forward than its upper chat. The bubbles have wrong distancing and roundings. Two messages have sharp corners.

3. Inside this video, the sidebar can cover status bar, which is odd. There is also another message that has too much rounding on the right corners. Additionally, the sticker that is sent, which is the main part of this mock-up, has no time tag.