Maybe, but I'm not persuaded. To some degree it depends what you mean by "grind" -- if you mean walking in a circle leveling up in order to advance I still think this is a major part of those games. But I think what many people mean is just the endless churn of random battles against low-difficulty enemies that operate as a slow attrition of short-term resources balanced against a slow addition of long-term power. You may be right that the battles are less miserable and marginally more tactical if you use your spells and items (though IIRC, many of these games had nothing other than healing items), but that is certainly how I remember playing them at the time -- particularly Dragon Warrior and FFI. It wasn't really until the 16-bit era that it made sense to stockpile spells for bosses because the 8-bit era didn't really have as many bosses. To me, the problem was that the battles were too frequent and too boring. Thus, for instance, the idea of playing Phantasy Star for 12 hours on a speedrun or 18 hours in normal gameplay is hardly appealing...
It's not that games like DW/FF/PS are tactically rich, it's that they are more about resource management (your second definition of grinding).
I can tell you from experience that Phantasy Star, Final Fantasy 1-3, and Dragon Warrior 2(*) require no grinding (as per your first definition) to get through the games.
(*)DW2 is the exception, where, through normal play, you will not be a high enough level to get through the final area. However, considering how massive the game is, it is balanced really well considering you can get through 90% of the game just by carefully choosing your battles, etc.
With Final Fantasy 1-3, a lot of magical equipment can be used in battle to cast spells, and while debuffing spells do not work reliably enough for them to be worth it, the buffing spells do work great, and they are a major component of getting through the game at lower levels.
Dragon Warrior is admittedly more about resource management, where you are literally sitting there determining the best order to take enemies down based on your damage output vs their defenses. A big part of this is the fact that characters will simply miss if their target is killed before they attack. A lot of people find this annoying now, but it was a crucial part of the resource management aspect of combat in those games. Getting out of combat with 10 more HPs due to choosing your targets wisely can often be enough to get you out safely. The man who developed these games was a hobbyist gambler, and a lot of the game can be explained that way. The dungeons in the early DW games are not funnels to take you to the next boss, but places full of treasure and danger, and the point is to push your resources (and a little luck) as far as you can, get the valuable stuff, and know when to get out and survive the trek home to regain resources. You aren't meant to take these dungeons down in a single attempt.
I mean, these games are not Wizard's Crown or even Pools of Radiance. However, they do have this reputation now of being linear games where you just go to town, go to dungeon, kill boss, go to next town, repeat, as you just hold down A or B during battle, then walk around in circles gaining levels when it gets too hard... and this is simply not true for a lot of the 8-bit console RPGs (as you mentioned, few of them even have very many bosses).
*The first DW/DQ indeed requires grinding (per your first definition) as no matter how well you know the game and how far you stretch your resources, you will hit a point (roughly 1/3rd into the game) where you are simply not powerful enough to make any progress. Note that the speed run Jason Liang linked is for the SFC remake, which "balances" the game to make it easier, from what I understand.