RAM/Storage are great upgrades because 5 years from now you can pop in 4x the capacity at a bargain since it's the "old slow type". CPUs don't really get the same growth in a socket's lifespan.
The technical differences between sockets aren't usually huge. Upgrade the memory standard here, add or remove PCIe lanes there. Using new cores with an older memory controller may or may not be doable, but it's quite simple to not connect all the PCIe lanes the die supports.
The RAM/SSD sure - a 2 TB consumer SSD wasn't even a possible thing to buy until a year after that laptop would have come out and you can get that for <$100 new now. It won't be the highest performing modern drive but it'll still max out the bus and be many times larger than the original drive. Swap equipment 3 years from now and that's also still a great usable drive rather than a museum piece. Upgrading to a CPU that you could have gotten around the time the laptop came out? Sure, it has twice as many cores... but it still has pretty bad multi core performance and a god awful perf/wattage ratio to be investing new money on a laptop for. It's also a bit of a dead end, in 3 years you'll now have 2 CPUs so ancient you can't really do much with them.
- Every time a new ToTL GPU comes out for a new family, buy it at retail price as soon as it launches (so, the first-available ToTL models that were big gains in perf: GTX 1080 Ti, RTX 2080 Ti, RTX 3090, RTX 4090)
- Every other release cycle, upgrade CPU to the ToTL consumer chip (eg on a 12900KS right now, HEDT like ThreadRipper is super expensive and not usually better for gaming or normal dev stuff). I was with Ryzen since 1800x -> 3950x -> 5950x but Intel is better for the particular game I play 90% of the time.
- Every time you upgrade, sell the stuff you've upgraded ASAP. If you do this right and never pay above MSRP for parts, you can usually keep running very high-end hardware for minimal TCO.
- Buy a great case, ToTL >1000w PSU (Seasonic or be quiet!), and ToTL cooling system (currently on half a dozen 140mm Noctua fans and a Corsair 420mm AIO). This should last at least 3 generations of upgrading the other stuff.
- Storage moves more slowly than the rest, and I've had cycles where I've re-used RAM as well, so again here go for the good stuff to maximize perf, but older SSDs work great for home servers or whatever else.
- Monitor and other peripherals are outside of the scope of this but should hopefully last at least 3 upgrade generations. I bit when OLED TVs supported 4K 120hz G-Sync, so I've got a 55" LG G1 that I'm still quite happy with and not wanting to immediately upgrade, though I do wish they made it in a 42" size, and 16:10 would be just perfect.