One of the great things about docker is/was that one can develop locally and the same thing would run when deployed. Having to run it on a distant machine kind of ruins this.
That's great, if you're doing something that will fit in a laptop. But I think the OP's point was that people using large datasets, complex workflows, or multiple projects, his method makes sense and saves money on buying new hardware.
For example, the web site I'm going to putz with today is many GB larger than the unformatted capacity of my laptop's SSD.
One could argue that even the "cheapest M1 + paying your remote Docker/Compute friendly machine" is not really the cheapest option. At least do not convince yourself "the new M1 chip is faster and will improve my developer experience regarding compute"
You don't buy a Mac because it's the "cheapest option". You buy it because you value several extra conveniences (displays, trackpads, speakers, construction, weight, baterry life, even keyboard - before and after they've messed theirs up for 3 years). Sure, it's not better in all of those than a comparable in price PC laptop, but it's usually better in most, and unaproachable in others. The SSDs it comes with are speedy as hell also (compared to the options Dell or Lenovo has on comparably priced models).
The CPU/GPU you can find in PC a too. At least until the M1, which has the best performance/power ratio of any current PC CPU. Plus there's always macOS, which lets you have a no-fuss desktop OS than runs all your proprietary apps and a native UNIX (as opposed to WSL/WSL2). Plus an ecosystem, drivers for your external peripherals (as opposed to the hit-and-miss Linux experience).
But it's not about saving money, and "I could the same work while spending less".
Obviously there are arm servers but they're not in widespread use.