I will say that "Outdated" and "Dangerous" is better for the community. I am thinking how to mark as helpful.

Outdated : You had explained
Dangerous : Actually, we know that there might be some worst idea in electrical things. Like as using 400 Volt for 3 AMP motor (my example might be wrong but I don't have much more idea of electrical things for now. Even I had seen some kind of "blast" with this example ~but I don't remember accurate number.)

Why would 8 bit microcontroller solutions be outdated? There are still enough 8 bit controllers out there, so I see no reason why solutions for 8 bit controllers would be marked as outdated

I don't have any idea if that's outdated but the OP knows more than me hence I am leaving the question to him... And outdated actually doesn't mean it won't work anymore. Outdated means new features won't work properly sometimes something might crash either. That's what "Outdated" represent.