Too much assistance on a GNSS approach?

I was flying into Marrakesh using the RNAV approach on Rwy 28

The designation states it is a GNSS approach. I thought this meant there would be no vertical guidance?

However, as I hit MX281 and began to manually fly the descent the autopilot captured the glidepath. Is this new? I remember a year ago that most RNAV approaches failed to provide any vertical guidance, whatever the variety. Has Asobo now decided to provide vertical guidance on all RNAV approaches?

Depends on the individual aircraft and avionics.

For instance the Garmin GNS530 won’t provide vertical guidance (at least they didn’t when I last used them, maybe WAAS units do?) Other Garmins such as the G1000 and some airliners will provide an internally calculated VNAV path, that may be flown by the AP in VNAV. And lastly, other airliners will calculate a path and enable the AP to fly it in Approach mode.

You’ll need to supply some more information for others to determine if there is an issue here or not. Aircraft type and/or avionics, as well as the engaged and armed FD/AP modes at a minimum.

I was in the modded TBM with the WT G3000. Approach mode had been selected so I guess your theory works out.