Zelda I may not have been harder, but the movement was more janky.
They both were hard. Unless you used Nintendo Power Hotline or some shit.
Those days, I never even got on the phone, unless it was to talk to Grandma or Mom or Dad.
In fact, I got a neat, little story about Zelda II:
I knew this kid, 15 years old, named Andre, I hung with him and another kid that was the same age as him, I was 8, but I played video games pretty good and I told them I could and so, one time he invited me to his apartment, well... his Mom's apartment! and I came and I did my shit, we played Double Dragon 2 and I was getting the hang of it, since I had played 1 in the arcades. We got to stage 6... that stage ended our shit so easily. It was something more advanced than all of the other stages. Nothing but seemingly precise jumps across revolving tracks. Nightmare shit with terrifying-death music. Must have been a design choice, lol.
Andre, lent me Zelda 2 after that time. I... accidentally deleted his save because I was not totally literate. I mean.. in Zelda 1, I was still saying "Master USENG AND U CAN HAVE DEES"
He was pissed off....big time.. he even talked to my Mom about the shit and... amazingly enough. They agreed I should hold onto the game until I could replicate the save... It was an almost perfect save, I believe, just missing 2 hearts, in the final part of the map.
Long-story-short? I spent a whole month ONLY playing Zelda II...I was playing this fucking thing the same way I played the First One... wee hours in the morning, in stealth.
In retrospect, I don't think it matters what age someone is, well... there has to be some kind of low threshold, right? but, damn.. I beat Blaster Master, Kid Icarus, Rygar, Iron Sword, W&W1(easier than Iron Sword) and so many others, before I even hit aged 10. Insane persistence and an industry still too young to produce the amounts of modern trash we have now.
I really need to just binge NES games again. I have 25+ and a toploader with HDMI mod. So it's not out of the question.