Catching Pokemon in Let’s Go looks to be very similar to PoGo. Combat against other trainers uses the traditional Pokemon battle system, though, so in that sense it’s definitely not as simplistic as PoGo. You have a team of six active Pokemon (everyone else hangs out in the bank) and combat is turn based with each Pokemon having up to four abilities that can change as they level up. I suppose there are some elements of that in PoGo but I find the tapfest combat much less satisfying than the main Pokemon games.
This game also features Mega Evolutions (temporary super powers for certain Pokemon), which is a cool extra layer of strategy when you’re deciding on your team. But it does not have the ability to breed Pokemon, so you kind of lose out on doing a lot of the unique combinations of Pokemon and abilities that you can usually only get from breeding. Unless there’s some other alternative here.
Very interested to see what next year’s Pokemon looks like. Game Freak says that the Let’s Go games may be a recurring series that is focused on introducing newer players to the series. I’m hopeful (but not really expecting) that this means the main Pokemon games will have less hand holding.