Controllers are not pilots (some are, but it's not a requirement and most
are not), and don't understand the nuances of things like GPS database
currency. Putting "VFR GPS" in the remarks, while having no official legal
significance, says to the controller, "I want to be given direct
clearances". You ask for them, he'll give then to you. Then it's up to
you to decide if you can safely execute them. If you can't, say, "unable",
and he'll come up with a different clearance.

That is exactly what I did the first time I got such a clearance. I was
told (this was being relayed by the class D airport's ground controller)
that I "should" be able to handle that clearance with "a GPS". (Note -
not "VFR GPS"; this had me wondering if ATC is even making any
distinction between IFR/non-IFR GPS!.)

Flustered, I canceled IFR and went VFR. A related factor was that that
routing was taking me excessively off-course, enough that I would have
then had to include a fuel stop. I knew I could get there faster VFR,
under the O'Hare bravo, and I did.

Holding altitude and heading are the two core fundamental skills of IFR
flying.

Yes, yes, yes, thank you. Ok, I had that coming.