stable's `pSpriteText` has a `TextConstantSpacing` flag, that is
selectively enabled for some usages. In particular, these are:
- mania combo counter (not yet implemented)
- taiko combo counter (not yet implemented)
- score counter
- accuracy counter
- scoreboard entries (not yet implemented)
Everything else uses non-fixed-width fonts.
Hilariously, `LegacySpinner` _tried_ to account for this by changing
`Font` to have `fixedWidth: false` specified, only to fail to notice
that `LegacySpriteText` changes `Font` in its BDL, making the property
set do precisely nothing. For this reason, attempting to set `Font`
on a `LegacySpriteText` will now throw.
Mixing `LegacySpriteText` with legitment fonts should never be the case,
so it's fine to consuder the height as the baseline, since there's
really no other way around it.