At the moment, I'm on a 6 year old (mid 2009) Macbook Pro with only 8 GB, 2.8 GHz Core 2 Duo [2 cores only vs your 8] and GeForce 9400M with 256 MB ... an old, underpowered machine - super underpowered compared to yours. And yet, AC 19 launches and opens a template and is ready to work in 90 seconds.
So, there must be something amiss in your installation including possibly permissions. Maybe a network issue? Might you have any networked libraries/etc loading?
One of the forum moderators • AC 26 USA and earlier • MacOS 11.6.8, iMac Pro