There are kits to upgrade the mini and studio to max out storage for reasonable prices. I've watched YT videos on the process and it doesn't look too hard.
As for the laptops, probably not feasible.
I will say that unlike laptops/desktops I used to buy before I went Apple, I use them for a really long time. When I ran Windows, I'd upgrade every few years. I had my Mac Pro 2012 for 9 years before upgrading to a Studio. Yes, I maxed out the storage, and it was annoying how expensive, but amortized over 9 years? Not as bad.
EDIT: if I was purchasing a Studio now, I'd likely do the 3rd party upgrade to 8TB (what I saw in a YT video). That's double what my M1 Studio maxed out at.
As for the laptops, probably not feasible.
I will say that unlike laptops/desktops I used to buy before I went Apple, I use them for a really long time. When I ran Windows, I'd upgrade every few years. I had my Mac Pro 2012 for 9 years before upgrading to a Studio. Yes, I maxed out the storage, and it was annoying how expensive, but amortized over 9 years? Not as bad.
EDIT: if I was purchasing a Studio now, I'd likely do the 3rd party upgrade to 8TB (what I saw in a YT video). That's double what my M1 Studio maxed out at.