They've still not fixed the Cyrodiil lag? It was the main thing that drew me to ESO (I found the PVE really dull) and had a lot of fun in Cyrodiil when it wasn't lagging. Sadly it lagged far too often and I gave up on the game several years ago. Have often thought about taking another look, but if they haven't fixed the lag it's rather pointless.
They replaced and upgraded the EU servers in April 2023, although I have never experienced any lag in several years (I play at 4k) and I suspect those that complain have potato PCs or bad internet connections.
In the last year they have also added AMD FSR, Nvidia DLSS, frame gen and multi-threaded CPU rendering, which help with performance.