chaowenguo Port maintainer reworked how the dotnet is installed and now is possible to have multiple versions of dotnet. We added dotnet8 as additional runtime:
$ dotnet --list-runtimes
Microsoft.AspNetCore.App 8.0.20 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.6 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 8.0.20 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.6 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
Check if your application can run now.