20+ hours into the game. For those not enjoying it make a b-line to part 3, you'll get some stuff that opens the game way up. For those who have watched gameplay, this is a terrible game to watch, I enjoyed it a lot while just chilling with my dog the most, the moment to moment gameplay really doesn't translate over video well.
Personally I'm really enjoying it, but it's not high art at all lmao, it's a ridiculous hiking simulator with really interesting cooperative online and kojimas super obvious and on the nose thematic story telling. Out of kojimas games it's currently my favorite but I really like games where I can plan to a very minute detail then put that plan in action. For me it's super fun to optimize a route, and have to adapt when shit goes wrong. If games had a thesis statement, this one's would be "it's about the journey, not the destination".
The game essentially makes the travel between objectives the main gameplay focus rather than whatever happens at those objectives like in most open world games. Personally I prefer this since travelling in most open world games sucks balls and is clearly there to pad game length, but if you're not the type that likes minute planning and slower cathartic gameplay it's totally understandable why you'd hate it
Edit: Also if I had to compare the game to something else, imagine early game Breath of the Wild, but you couldn't upgrade your stamina or get abilities that easily let you circumvent environment obstacles. This game feels a lot like that but more drawn out.