This was meant to be an optimisation to allow the background to load
while the intro is playing, but as the current default intro loads a
background itself, this was rarely the case and also counter-productive
as it would bypass the equality check and start a second load sequence.
Rather than fiddling around with the activation modes, this seems like a
much cleaner way to make things work.
Closes https://github.com/ppy/osu/issues/18277.