The feature is good in itself, but as you can see, some people use the same background and foreground color on purpose.
it should never have been the case that users with one color scheme cannot read text from those with a different color scheme
It has been like that for years and noone seems to complain
Imo, the feature should be applied regardeless of how the line is, but it have to be optionnal (per channel and per network would be really good) or you will have frustrated users
Making this an option would result in more display inconsistency across clients unfortunately.
Not sure how, people that don't want the feature will just disable it and will see the message as usual, others will make use of the feature.Most users are already overriding the display with a script and are already displaying a different line comparing to the original anyway