Libgcc: new version won't deactivate the old version

[Michael]

> --->  Computing dependencies for libgcc
> The following dependencies will be installed:  libgcc10
> Continue? [Y/n]: y
> --->  Activating libgcc10 @10.2.0_3
> Error: Failed to activate libgcc10: Image error: /opt/local/include/gcc/c++/algorithm is being used by the active libgcc port.  Please deactivate this port first, or use 'port -f activate libgcc10' to force the activation.

Is there a reason that trying to activate the new libgcc does not deactivate the old libgcc?