I somehow got into a situation where trying to open any Unity project would crash immediately with:
received signal from system: SIGSEGV
Stack trace:
0x00007ff618eeff28 (Unity) [StackWalker.cpp:961] StackWalker::GetCurrentCallstack
0x00007ff618efcf22 (Unity) [StackWalker.cpp:939] StackWalker::ShowCallstack
0x00007ff61c14e7df (Unity) [Stacktrace.cpp:142] GetStacktrace
0x00007ff618ef9750 (Unity) [CrashHandler.cpp:26] winutils::PrintStackTrace
0x00007ff618eee3a5 (Unity) [CrashHandler.cpp:100] winutils::CrashHandler::DefaultSignalHandler
0x00007ff621202163 (Unity) seh_filter_exe
0x00007ff62291af98 (Unity) _longjmp_internal
0x00007ff6211140eb (Unity) _C_specific_handler
0x00007ff8048011ff (ntdll) _chkstk
0x00007ff8047ca289 (ntdll) RtlRaiseException
0x00007ff8047ffe6e (ntdll) KiUserExceptionDispatcher
0x00007ff6166e081f (Unity) [DynamicHeapAllocator.cpp:255] DynamicHeapAllocator::InitializeMemoryBlock
0x00007ff6166e23f7 (Unity) [DynamicHeapAllocator.cpp:207] DynamicHeapAllocator::RequestLargeAllocMemory
0x00007ff6166dac15 (Unity) [DynamicHeapAllocator.cpp:475] DynamicHeapAllocator::Allocate
0x00007ff61668f38d (Unity) [MemoryManager.cpp:1634] MemoryManager::Allocate
0x00007ff6166b3981 (Unity) [MemoryManager.cpp:352] malloc_internal
0x00007ff618310920 (Unity) [dynamic_array.cpp:17] dynamic_array_detail::dynamic_array_data::reserve
0x00007ff61ce3b212 (Unity) [ProfilerHistory.cpp:36] ProfilerHistory::ProfilerHistory
0x00007ff61ce706e4 (Unity) [ProfilerSession.cpp:47] profiling::ProfilerSession::ProfilerSession
0x00007ff61ce7729a (Unity) [ProfilerSession.cpp:63] profiling::ProfilerSession::Initialize
0x00007ff617abbce1 (Unity) [Profiler.cpp:197] profiler_initialize
0x00007ff617ab5773 (Unity) [Profiler.cpp:49] StaticInitializeProfiler
0x00007ff618218e31 (Unity) [RegisterRuntimeInitializeAndCleanup.cpp:70] RegisterRuntimeInitializeAndCleanup::ExecuteInitializations
0x00007ff6179eb12c (Unity) [Player.cpp:642] RuntimeInitialize
0x00007ff61c16935a (Unity) [WinEditorMain.cpp:798] WinMain
0x00007ff62108e832 (Unity) _isa_available_init
0x00007ff62108e71e (Unity) _isa_available_init
0x00007ff62108e5de (Unity) _isa_available_init
0x00007ff62108e8c9 (Unity) WinMainCRTStartup
0x00007ff8045c7bd4 (KERNEL32) BaseThreadInitThunk
0x00007ff8047cced1 (ntdll) RtlUserThreadStart

I tried restarting my computer, cleaning up my temp directory, killing any other running processes, etc. and nothing. Every Unity version I have on my machine fails to open and crashes immediately with that callstack even before Editor.log is created.

Update: this happened after calling ProfilerUserSettings.set_frameCount with a very large value, which saves that value to a registry key that seems to be shared across all Unity versions.