With stock bodywork it’s a struggle to fit much more than a 235 track tyre(thanks gc3!) on an e36. Regardless, switching to the same size in a 595 or similar has roughly doubled the longevity on track because the compound can deal with the temperature. No good for autocross I guess because they need a bit of heat. The smaller tyre reduces unsprung mass/rolling resistance and can deal with uneven road surfaces and the wet (we get a lot of that!) better.
Every car/driver/track is different and if you are able to run a wide enough tyre maybe it can dissipate the heat sufficiently. Road use or autocross isn’t going to upset an R888 either. Like for like though, R888’s definitely have a reputation for being soft, so they work great from cold, but melt after a few laps. No-one cared here when they were cheap, but they certainly don’t dominate the paddock anymore.