Time will tell, but I'm inclined to agree it occupies a distinctive slot in the '911' legacy. I had multiple dd SCs, then a track car, then two purpose built 911SC racecars for PCA competition (was 'G' stock, now 'D' under latest classification) They make very fast, competent racers, but also require a pretty distinctive set of driving techniques. It was no coincidence Mark Donahue walked away with the title in the initial IROC series in RSRs; it took all those other star drivers a full season to figure out how to make a 911 go fast. I got a 993 Cup Car after I'd spent some time in Formula cars, and I was stunned at how much easier (and how much more capable) it was than the early cars. Having a 'proper' multi-link rear suspension is a BIG deal. It is as light and nimble as the early cars, with gobs more power, sensational brakes (tho all 911s are brilliant under braking, their one standout quality) but also the ability to place it anywhere on the track, at any time. So all the charm and personality of the older cars, but with a thoroughly modern suspension. Now, collectibility is not really about performance, and much more about personality etc, so we will see if that translates to desirability. But early returns are positive!
I have been a Porsche fan for a very long time, but until recently, never had the opportunity to ride in one (still haven't driven one to my dismay). A coworker finally finished restoring his '67 911S so I was thrilled to go for an extended ride. I have no modern Porsche to compare it to so impressions are limited to this car. The skinny tires make the car wander and the noise from the rear is always there, but when he hit 7K the sound was incredible. I hope one day to own any 911, probably not an early one, but one of the air-cooled ones eventually.
I currently own one of both, a 1988 911 Cab for weekend fun and a 2012 991C2s as my DD. The 991 is far superior car in every measurable category. But the old school air/oil cooled 911 trumps it in fun and driver involvement. I used a 993 as my DD back in the 90s, and while it was more involving than my 991, its still not as much fun and involving as the 911...