I never encountered this game upon its release. Then I was high in Spectrum heaven, while my Master System-owning mate was only really interested in arcade stuff like Rampage and Thunderblade. But years later I picked up the third game in the series, the (now maligned) Phantasy Star III, which I played to death over the course of a summer. More of that on another occasion, but PSIII introduced me well to the universe in which the series is set, as well as the combat system and game structure. Hence when I finally got round to Phantasy Star proper it was like revisiting an old, kindly friend.
In short, there was nothing on the NES that could hold a candle to it. It's just a shame it didn't help shift Master Systems in massive numbers, nor at the time was it particularly well-regarded in Europe. A pity, because it plays well and there are hours of exploring to be had. A true classic, in other words.
While you might argue it's difficult to understand how the mechanics of an RPG can work without a numbers system underpinning it, the game works to normalise the planning and execution of accumulation strategies semi-independently of the tightly-structured story (being an early JRPG, there are no side-quests to speak of). It simulates and inculcates habits that underpin actually existing economic relationships. Neoliberal sensibilities also work on the surface of the game as well. As you walk your way through the three worlds, you get a sense of how sparse they are. Considering you're part of a space-faring civilisation, towns are few and far between and they're sparsely populated. You visit and very little, if anything, changes between trips. An area might have been unlocked because of actions taken elsewhere, but the same people stand around in the same places and have exactly the same snippets of information to say. True, there was only so much cartridge space Sega had to play with, yet the effect is a world where you're the only active element. Nothing is time limited. The quest is still there if you decide to spend 20 hours knocking around the backwoods of the ice planet hunting for White and Blue Dragons - and by extension, experience points.
When you assume the mantle of Alis and accept her quest to avenge her brother, you're playing her role. And on top of that, you're roleplaying a banal, oft-unremarked, but absolutely crucial constituent of neoliberal consumer culture.