The 2010 Galaxy S had a 233 PPI display compared to the 326 PPI that Apple marketed as "Retina". The 2011 Galaxy II actually regressed slightly to a 217 PPI display. These were both PenTile displays, so their effective PPI was definitely noticeably lower than the paper specs would suggest.
Even in 2012 with the Galaxy III, Samsung's mainstream flagship reached 306 PPI, which is still less than 326, but it would be roughly comparable if not for the compromised PenTile subpixel arrangement that means it didn't even have 306 PPI of clarity, nowhere near as good as a 306 PPI traditional LCD in terms of clarity.
By 2013 with the Galaxy S4, Samsung finally exceeded 326PPI with their 441 PPI display... on paper, but this was still a SAMOLED screen with a PenTile arrangement, but it was probably comparable with the 326 PPI of the iPhone 4.
The 2013 HTC One (M7) actually did have a 468 PPI Super LCD screen, which was impressively sharp, but still years later than the iPhone 4.
It took several years for the mainstream competition to catch up to Apple's retina displays. Apple was miles ahead of everything else. And I say this as someone who was an Android user until the iPhone X! I was not an iPhone user, but I could easily see how much better the pixel density was on iPhone 4 and for several years after that. As with most things, there are diminishing returns, and having a 20,000 PPI display next to a 500 PPI display is going to be completely unnoticeable. 326 "real" PPI is an excellent level of clarity, and I don't see much (if any) advantage to going past the ~450 PenTile PPI (whatever that works out to in real PPI) that we have on a lot of mainstream smartphones today.
Maybe you fell for the marketing hype of PenTile displays that were claiming higher PPIs than they actually had?