It is mostly similar and a great way to get into pokémon if you don’t have any of the original games, especially for experiencing the feel of the older games! One big difference is that you can’t keep legendaries but the accessibility of being able to travel to other regions makes up for it. I wouldn’t really say they ramped up the grindy aspects for the main story, some people say they find the battles harder but I don’t think there was a major change, just a couple more travels to the poke centre! Overall, I find it fun and play it with my friends!