Unfortunately, embedded systems programming has always been on-topic at SO. It's a scope overlap with this site. As one of the few who actively user-moderate the embedded tag there, I believe this was a big mistake.
Because embedded systems questions - particularly trouble-shooting ones - could either be about software or hardware. And as soon as you discover that your problem is in hardware, the question suddenly turns off-topic. Very awkward situation. Those questions would be in a much better place on this site. And then of course on SO you always get the occasional clueless PC programmer showing up to answer embedded systems questions, with post quality ranging from mildly useless to blatantly incorrect.
And then of course we have the random clueless people who ask pure electronics hardware questions on SO thinking it is ok somehow. Because of this I recently pushed to have the electronics tag purged and the community agreed. So that should hopefully be a little bit of on-topic traffic coming this way instead.
But it's too late to fix SO now, it is what it is - embedded systems questions are on-topic there, including microcontroller programming and HDL languages. And therefore that site needs ADC, FPGA, ASIC etc tags too. At any rate, such things should be discussed at SO.
I think it takes a new site to fix this: when we launched the software development & electrical engineering communities at Codidact, I insisted to keep embedded systems on the software site and have those asked at the EE site instead, with no scope overlap. Though if that separation of topics will work out better is too early to tell, since the site is still young. If it works well, then that's evidence that SE could benefit from the same - time will tell.