Harsher measures against inactive players?

I'm really tired of people who don't start games, or people who ask for a rematch and then don't start the game, and tangentially, people who wait it out instead of resigning. All of these things make me sit and twiddle my thumbs while waiting to start a new game. Why do people do this? It appears that the "temporary ban" is not very effective because this happens very often to me.

Problems with internet connection. It's not players' fault! Temporary ban is sufficient.

Why is it that their internet connection so often fails when they are in a losing position?

Because of selectivity of memory. You remember all the instances when opponents' internet connection failed in a losing position and forget all the other instances.

Really? How often do internet connections fail anyway? Mine basically never fails, and yet I am experiencing this phenomenon in maybe 10% of the games I am in.

Depends where you are located. The weather is not the same everywhere in the world. Also, technology is not the same and distance from France (where lichess servers are located) is not the same.
www.accuweather.com/en/weather-news/top-5-most-vulnerable-us-cities-to-hurricanes-atlantic-tropical-season/48281135

Yeah, but most of the time, when a player is in a losing position and does not move, I can hover over their username to see that they have "excellent connection".

Some people just don't know how to accept a loss. Not moving and wasting your opponent's time shows just how much they care about good sportsmanship. I would block such people.

Sometime，network lag，so Did not start.