I went through a few YouTube videos the other day comparing controllers. Sadly, for each of them was a brain dead reviewer complaining how you they don't have 3 hands and can't reach the D-Pad and who obviously never played on the N64. Personally, I found the N64 controller to be the most comfortable controller I've ever held. I'll always miss the Z-trigger and wish it could come back. But alas.
One thing I can't argue, though, is that the D-pad and L button didn't see much use. I think the only game I ever used it extensively was Doom 64. However, now a N64 layout makes a little more sense, doesn't it? Back in the 32/64 bit era it was all about ugly polygons and 3D graphics. It's a prime reason why it's easily my least favorite generation. 2D platformers went from the dominant genre to near extinct in the space of a year and the N64 was no exception. Off the top of my head I can only think of Nintendo itself releasing only released Yoshi's Story and Kirby 64, though I might have forgotten one. In the end, the Tri-handled layout didn't amount to much more than a legacy of idiotic YouTubers.
Fast forward to 2018 and the market is totally different. All consoles are flooded with games where D-Pads are often the better option as they're just faster and more responsive than an analog stick. This works well for Sony as their lousy controller layout has always had the analog stick in the secondary position making it default worst controller every generation for almost 25 years (fight me) and now their dumb decision at least helps with some games.
However, Nintendo and Microsoft have the D-pad in a secondary position. It's functional, but not optimal. And here's where the N64 controller was ahead of its time. If released today (naturally upgraded with modern bells and whistles), I would probably use the D-Pad grip in a solid 1/3 of the games I possess. The option of a simple and comfortable D-pad-centric grip has merit and would fit in beautifully within modern gaming. I know that if I could use the N64 controller with the recent Mega Man demo, I would choose it over my Pro Controller without a second thought.
It's just unfortunate circumstance that the N64 tried it 20 years too early because as wonderful as the N64 controller was when it was released, its unique design would be a revelation today, fixing one of console gaming's biggest problems.