I'll be honest with you. I own about four or five different GameBoys and have them on display along with dozens of other gaming memorabilia. I'm a huge game nerd, and I'm especially fond of the 90s. That's a big shocker, right? Of course I would love the games from the era from when I grew up. I say all this so you know that I'm biased, but the 90s had some amazing games.
The fact that people still choose to mod systems to play these old games on new systems is proof that the games endure. Maybe controllers and graphics are better nowadays, but the classics are classic for a reason. The gameplay is timeless. Sure, the GameBoy only had two buttons and a horrible screen, but it's still the absolute best as long as you get past those two things.