The Arduino SDK is the simplest to use, sure, but the Pico framework (I don't have experience with the Espressif one) is extremely good, and the Pico's PIO is a godsend. I used it to implement 3 wire SPI (data bidirectional on the same wire) at almost 'real-time', which is to say, at half the speed of the hardware SPI controller (half the speed because the interface clock is put up one cycle and down the next; this also gives enough time for data shuffling).
Why does the Arduino SDK necessitate a huge markup on Arduino boards, when $0 of every computer I buy to run Linux on goes to GCC?
I'm not expecting a $0 markup, but Arduino prices are simply unreasonable for what they offer, especially if you live in a lower income country.
Arduino targets the hobyist market where customers will buy one (or at best a handful) of their boards. Arduino simply has no other way of recouping their investment than selling expensive hardware.
So I don't think it's fair to say that Arduino is being greedy. Also FWIW, Espressif's official dev boards are also pretty expensive. Not Arduino expensive, but several times the price of identical "clones" based on the same reference design and using the same official esp32 module.
Generics may have the same active ingredient but (vastly) different pharmacokinetics - i.e. different absorption rates/retention in the body. For basic stuff such as painkillers that's one thing, but for more sensitive medication such as insulin, antidepressants or anything related to the cardiovascular system (heart rate, blood pressure and clotting) one has to be very careful when switching between brands.
So can the Pi Pico, the Milk-V Duo (one 64 bit Linux core, one 64 bit microcontroller core), and many others.