Is Lichess lagging?Measurements in progress...No. And your network is good.No. But your network is bad.Yes. It will be fixed soon!
Lichess server latency
The time it takes to process a move on the server. It's the same for everybody, and only depends on the server load. The more players and the higher it gets, but Lichess developers do their best to keep it low. It rarely exceeds 10ms.
Network between Lichess and you
The time it takes to send a move from your computer to Lichess server, and get the response back. It's specific to your distance to Lichess (France), and to the quality of your Internet connection. Lichess developers can not fix your wifi or make light go faster.
You can find both these values at any time, by clicking your username in the top bar.
Lichess compensates network lag. This includes sustained lag and occasional lag spikes. There are limits and heuristics based on time control and the compensated lag so far, so that the result should feel reasonable for both players. As a result, having a higher network lag than your opponent is not a handicap!