Gonna have to completely disagree. I do exactly s you say, and I gave up on upgrading suits / weapons.
In how many hours of playing?
In the 6 or so actual hours of gameplay, ive manager to buy a G2 suit but I havent even gotten anything for upgrading them due to the brokenness of the game. I have compeltely written off engineering my suits and weapons entirely due to the ridiculous amount of hours it would take.
Im sorry but I dont buy it when you say 'minimal grinding. To me 'minimal grinding' is less than 2 hours of play every 2 or 3 days. anything more than that is more than 'Minimal' grinding.
The key is work smart and efficiently, not hard.
I'll give you a tip, since the pre-upgraded gear only spawn once a week after the Thursday tick, if you're late, go out to far flung planetary bases as very few if any players could have visited them in that short time. I went out searching 3 days after the first server tick, all of the gear in major stations were gone by that point. I opened eddb, look up all nearest starports and went out to bases >10k Ls away and in just 3 hours time, I got most of the gear I was looking for (I wasn't looking for plasma stuff). And in that 3 hours, most of the time I was reading while supercruise assist took over the job of flying.
As for grinding, what are your definitions of 'grinding' exactly? Personally, I define grinding as a repetitive and boring chore such as logging in and out again for materials. In that case, the only 'grinding' I did was for a couple of manufacturing instructions. The other items I obtain through efficiently pillaging settlements, taking missions and trading all of my lower grade items for higher ones. In my observation from watching some other people play the game, I will admit that I may be going through bases a bit quicker than the average. It takes me roughly 5 minutes to completely pillage a settlement of all of its useful items. Plus, just after the first dozen missions, I've already memorized the locations of all of the useful drops in the settlements.
As for playtime, I will admit, I am a lot more free that most people as I'm still a student who has just recently finished his finals. (+Covid, country in full lockdown, can't do anything) So... let's just say 9-ish hours a day for the past week, that's still way off from what took Jingles a week to accomplish. Remember, the upgrade costs are exponential, G1 to G2 is nothing compared to G4 to G5. If it took me 60-70 hours to upgrade 2 weapons and 1 suit to G5 and 2 suits to G3 + a little bit of engineering, my guesstimate of 10-20 hours Jingles took to get from G1 to G2 is painfully slow, and judging from his methods, yeah, I can see why. I've not encounter any of the problems Jingles struggled with, mainly scavengers as I've discovered that I'm actually decently proficient at FPS despite the last time I played FPS was 5 years ago and was horrible at it. I never found FPS to be a problem and scavengers are usually swiftly dealt with using handheld weapons without any issues.
TLDR, Jingles' methods are horribly inefficient whereas I maximized speed and utilized method optimization. (plus a certain level of skill I guess...)