I ran into the same thermal issues on the XPS 8950. I purchased the Dell premium air cooler from the big online store. The Dell premium air cooler significantly lowered my cpu temps at 100% load as well as at idle. Using the Dell premium cooler also avoided the fan errors during boot. Simple swap. I am pleased with the result. I hope this helps.
My brand new XPS 8950's CPU is running quite hot under fairly minimal loads when gaming. According to MSI Afterburner, my CPU load sits around 30 percent in demanding games. When playing Warzone with 110 FPS on Ultra graphics settings, the CPU is running in the mid 80s C. Valorant at 120 FPS with graphics setting maxxed puts my CPU temp in the mid to high 70s. Mount and Blade 2 Bannerlord on high graphics settings at 60 fps runs at 85 C in battles and 70s C out of battle. Are these safe temps to be at while gaming for several hours at a time? Gaming is the most intensive thing I do on the machine. I know the stock fan on this PC has been widely panned,  but I'm hesitant to install a new one unless absolutey necessary.  My specs: Intel Core i7 12th Gen 12700 2.10GHz Processor NVIDIA GeForce RTX 3060 32GB DDR5-4400 RAM
XPS 8950: CPU runs hot when gaming. Am I safe?