Yeh the obscelescence is built in because peopel are going to throw it out and upgrade to a new model anyway/it's a conspiracy theory to force you to upgrade.
I had a similar experience with Surface Pros, aside from the being satisfied with it part XD Got one to try out because the hybird tablet/laptop thing was intrigueing but it couldn't really do the things I needed it to do (which in its defence is probably more than most people that would get such a device would ask of it) and also I just really, really, really hate Microsoft (it had been literal decades since I last used Windows so I was like well maybe things are different now and nope I still hate it). After some time I replaced the Surface Pro with my MacBook Air and was trying to figure out what to do with it when it made the decision for me by expanding the battery alarmingly and was summarily dispatched.
My big rigs and phones are always the highest end things I can afford at the time (the big rigs for the kind of work that I do and the phones it's mostly the camera specs and internal storage that kill me pricewise), the laptops are the ones I'm constantly arguing with myself about as my instincts are to do the same again and just get the highest spec one I can afford, but in reality I don't need the highest spec one I can afford as it's not my main rig and I only extensively use it once every couple of years. The rest of the time it's been whenever I've been at work waiting for the bigs to finish up doing roleplaying notes and hiving and this year lesson planning.
And that was how I ended up with a MacBook Air instead of a MacBook Pro XD
But the idea is that I should be able to sit on the thing for at least 5 years before I have to start thinking about replacing and I've usually gotten at least that out of the Apple devices that I've owned over time (I am pretty sure my Surface Pro lasted about as long as yours, and I can't remember how long my last Fitbit lasted, the current one will be entering its fifth year soon).
Which has led me on to completely switching systems in the near future for pretty much the exact complaint you were writing about. My next laptop is going to be one of these. I still haven't decided whether I'm going to get a 13 or 16, I love the smaller form factor and lighter weight of the 13 and 11-13 is what I've always had with laptops, but the 16 has so many more cool things. I'm planning on running Arch Linux + KDE (same as my big rig) on it and the modularity means that like my big rig I should only have to replace parts moving forward as opposed to throwing out the whole unit and getting another one.
My next phone is going to be one of these and currently this is my next watch (aaaaahhh wish me luck with the last two whenever I get them XD).
Hope the new laptop works flawlessly and does everything you want for ages and ages and ages :D