This isn't really accurate for the SP8 or 9. I used an 8 as my daily driver for dev work for 8 months, and it handled everything I threw at it, including building a monolithic repo I have to deal with at work with dozens of projects inside, something my Surface Laptop 3 struggled hard with.

It sounds like you haven't used one in a few years. That was absolutely true 5-7 years ago. The Surface Pro 8 and 9 (Intel, not ARM) are extremely capable laptops. I just sold my 8 recently, not because it couldn't* serve as my main dev machine, but because I just didn't love the form factor. The keyboard was surprisingly solid, but the inability to pick it up easily with one hand is what finally pushed me back to a clamshell style laptop.

Hardware wise though, the Pro 8 was one of the best PCs I've had, and the 9 is supposed to be even better.

Edit: a word