It is a pain in the ass. I race mostly in ACC and driving on a straight while lapping drivers, changing gears, configuring tyre pressures adjustments meanwhile I'm mentally calculating how much fuel I would need to add to finish the next stint is an absurd mental overload.
I used to have time to spend hours and hours making setups, understanding what setup changes made every physics engine click, creating excel worksheets, creating very convoluted motec worksheets, analysing data deeply (I enjoy that quite a lot to be honest), making really time consuming tyre life tests under different temperatures..., I used to love that, I got older and sadly I no longer have time for all that. And no longer do I want to do all that massive amount of work just to do a 3 hour race with a setup that I like and a strategy that will work fine.
Nowadays I no longer can afford to be race car driver, telemetrist, strategy engineer and setup engineer all that at the same time and what is worse: without proper tools/data. It is also insulting to have online races in where 1 or 2 team mates are just watching the race and making some calculations only to at the end of the stint have to let the driver do all the configuration work by himself risking a crash while multitasking over 250km/h.