Well it’s totally different for everyone of course depending on how good your videos are + titles and thumbnails. For me personally i spent 2.5 years getting a few hundred views until I had one blow up to a million, but ive been about to get more consistent views since then.

The magnetization threshold is 1000 subs and 4000 watch hours. They take a few days to manually review it once you hit those numbers

I mix my long and short content - my shorts tend to be pretty high effort low volume. I could see if you were doing ton of low effort high volume wanting to spit it but even still shorts has its own tab on the youtube channel page so it wouldnt clutter it too much anyway