I was trying out my Mavic Mini. Big day. In the town. Straight up, altitude 50 m. Connection lost. Don't even think to fly away, keep above and connection lost.

Towns will have a lot of wifi interference. But regardless of that, in most places it’s illegal to be flying drones above a town so not an issue

Hi there, if the drone was flying above the RC, please place the antenna horizontally for the optimal transmission zone. Please check the screenshot below.

In the settings menu, you can look at the relative signal strengths of nearby wifi versus the drone-RC link.  I think you can select a different channel if the auto mode hasn't selected a channel with the least interference.  Perhaps that might help, or at least you could check to see if you have a good clear channel before flying in a particular area.

No problems outside the city, the signal is more than enough for this toy. But in the city... yep, kinda sux. Especially in areas that are very crowded, lots of wifi signals, gsm antennas, buildings etc.
I tried it in a zone that even at 25-30m the connection started to be unreliable...