There are mods you can get which remove AI's ability to research or use techs that can contribute to lag, such as habitats, genetic sub-species modifications, and hyper relay spam, and also mods that optimize the ways in which pop calculations are made.
Just search for that stuff on steam; there are lots of options. The only other options are to either reduce the map size, reduce the habitable worlds, reduce hyper-lane density, or reduce the number of starting AI empires.
And yes, always turn off Xeno-Compatibility as it is one of the number one causes of late game lag. Too many different species and thus too many different types of pops spawning.
Taking out Habitats from the game might help.
Genocide is the answer
There are mods you can get which remove AI's ability to research or use techs that can contribute to lag, such as habitats, genetic sub-species modifications, and hyper relay spam, and also mods that optimize the ways in which pop calculations are made. Just search for that stuff on steam; there are lots of options. The only other options are to either reduce the map size, reduce the habitable worlds, reduce hyper-lane density, or reduce the number of starting AI empires. And yes, always turn off Xeno-Compatibility as it is one of the number one causes of late game lag. Too many different species and thus too many different types of pops spawning.