Can’t read the yellow warning text on your light coloured terminal, outputted by the various systemd utilities such as journalctl, systemctl, hostnamectl, etc.? I got fed up with copy and pasting this text into a text editor to make it legible, and added a new environment variable, SYSTEMD_COLORS=auto-16, which causes it to use your terminal’s ANSI yellow (which presumably you already have configured to a readable colour). #systemd260
This will be available from systemd version 260 (but you can set it now; it won’t do any harm). Full documentation: https://www.freedesktop.org/software/systemd/man/devel/systemd.html#%24SYSTEMD_COLORS
Another alternative would be to set a background colour for coloured text, but some people would consider that ugly. I don’t think there’s solution that makes everyone happy.
Finally, if your terminal’s ANSI yellow isn’t readable, maybe see https://www.mavit.org.uk/termcolours/ or https://www.mavit.org.uk/tango-putty/
The question remains, is it a good idea to have an “unbreak this broken behaviour” setting? One alternative would be to make SYSTEMD_COLORS=auto-16 the default, but that fails for people who don’t have the ANSI colours in their terminal configured for good contrast (some well-known terminals, such as PuTTY and XTerm, still have poor defaults for this use-case, for one colour or another).