Just for perspective, a thought experiment:
Assume a 170# “FAA standard” pilot and a magical 30# aircraft, or a 200# pilot and even more magical zero weight aircraft, either way, 200# gross weight. Then assume a 20 mph (30fps) airspeed, about what a paraglider does and probably the lower limit for safe handling in anything but dead calm conditions. Finally, assume a high end sailplane L/D ratio of 50:1, which means slick composites which weigh a lot more than zero or even 30 lbs, but hey, it’s a thought experiment:
So, with a 200# weight and 50:1 L/D, that’s 4# of drag which means 4# thrust, 120lb-ft/s or 0.22HP or 163W, just to maintain level flight. If you want an abysmal 50fpm climb, that requires an additional 0.3HP or 226W, so now you’re up to over 1/2HP.
And, that’s assuming 100% efficiency in the drivetrain and propeller, also not realistic.
So, the point of all this is that while it’s certainly possible to build a HPA that will fly, and even meet some narrowly defined task, it can never be practical even for any kind of sport flying.
Unless you consider a foot launched hang- or paraglider to be a HPA, but only if you carry it and hike to the mountain top, no driving allowed.