Gargoyles was made to go head to head with batman tas and they both did a great job of going right to the end of the line of what a tv-y7 could get away with(and probably couldnt get away with today). That said like Batman they both were designed to target kids and for all the brilliance there were episodes that skewed a little younger, and little touches like how shows of that era had to dance around words like "kill".

In addition to the usual stigmas surrounding animation I wonder if another factor in this is that it's a pure Disney branded product. While they have plenty of edgier stuff in their back catalog that should let people know their cartoons arent just for small children, the rep is there and they may not be ready to put out a tv-14 or even tv-pg cartoon that targets young adults and teens. It was find when its some licensed anime on d+, or if it's star wars or marvel, but this is a pure Disney badge.

Of course theres also the usual explanation of cost. Good animation costs a lot of money to produce and while lord knows disney has the cash it might be cheaper for them to just shoot this series in front of the giant tv. I feel like a show with characters like the gargoyales would be counter productive to be live action since they regularly fly, and would need expensive suits or full cgi anyway to work, but I suspect they do the math and no an effects guy is cheaper than a team of animators.