The seats are assigned. People have been standing in line for 15 minutes now. Why on earth would anyone want to stand there, when they could just sit and wait until the line clears?
I understand wanting to get off a plane ASAP, but boarding? You just end up sitting on the plane, waiting for everyone else to get on.
Okay, I am willing to argue:
German Luftfahr Bundesamt (Federal Airfare) allows up to 100Wh of Li-Ion in checked baggage: https://www.lba.de/DE/Luftfahrtunternehmen/Gefahrgut/Passagierinformation/Passagiergepaeck/Elektronische_Geraete.html
Both hand and checked baggage:
Anything else you wanna argue is not true?
Also Lufthansa: Baggage battery restrictions.pdf
And Eurowings: Restrictions dangerous goods
Condor prohibits anything more than a smartphone: Condor restrictions
Anyway I think I made my point: It depends on the airline.
So go check with them if you travel!