> Assuming I don't drop this computer and smash it to bits, I'll be able to keep it as long as my last MBP (a 2015 I bought new). So conservatively, let's say 5 years.

The benchmark is not whether your existing computer breaks to pieces, but whether it can do that "1) Browsing 2) Coding 3) Video and photo editing 4) Graphic design" smoothly for the coming 5 years in the newest versions of popular applications, as they inevitably get more demanding for older hardware.

That being said, I don't think the SaaS-part of the value proposition is particularly convincing, and there barely is anything else.