128GB PC laptops are not very cheap either, if you want a decent one, like a ThinkPad.
Here’s a 7000 USD ThinkPad P16 Gen 2 workstation:
https://www.lenovo.com/us/en/p/laptops/thinkpad/thinkpadp/th...
Maybe, but it's 1) ARM 2) In a Mac. Those are some colossal caveats.
I understand the problems of measuring cross-platform performance but anecdotally even on things that it's not specifically optimized for, for example running a Java Virtual Machine with 10s of GBs of memory, it's really fast, efficient and competitive to most non-Mac/ARM setups.