How to reproduce:
1. Open the attached "ShaderCrashRepro" project
2. Open Project Settings… > Graphics
3. Press Save to asset
4. Save and replace the existing Shader variants
5. Press Clear

Reproducible with: 2022.3.28f1, 2022.3.32f1, 6000.0.5f1
Not reproducible with: 2021.3.39f1, 2022.3.27f1

Reproducible on: macOS 14.5 Sonoma (Intel), Windows 11 (reported by user)
Not reproducible on: No other environment tested

First few lines of stack trace:
0x00007ff62b71de1a (Unity) free_alloc_internal
0x00007ff62aff9f91 (Unity) core::vector<void * __ptr64 [38],0>::~vector<void * __ptr64 [38],0>
0x00007ff62bbd0fe7 (Unity) std::_Tree_val<std::_Tree_simple_types<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo> > >::_Erase_tree<std::allocator<std::_Tree_node<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo>,void * __ptr64> > >
0x00007ff62bbd0fcf (Unity) std::_Tree_val<std::_Tree_simple_types<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo> > >::_Erase_tree<std::allocator<std::_Tree_node<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo>,void * __ptr64> > >
0x00007ff62bbd0fcf (Unity) std::_Tree_val<std::_Tree_simple_types<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo> > >::_Erase_tree<std::allocator<std::_Tree_node<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo>,void * __ptr64> > >
0x00007ff62bbd0fcf (Unity) std::_Tree_val<std::_Tree_simple_types<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo> > >::_Erase_tree<std::allocator<std::_Tree_node<std::pair<PPtr<Shader> const ,ShaderVariantCollection::ShaderInfo>,void * __ptr64> > >
0x00007ff62bbd557d (Unity) ShaderVariantCollection::ClearVariants