It’s a shop - it’s all about speed here. If you can suck the oil out then there’s no need to drop the pan. And you’d have to drop the pan to get to the filter.
And 2019s don’t have a drain plug. Chevy has to make it hard. Plus look at the exhaust pipe, right in the way so you can’t easily drop the pan. I hate engineers.
Why dont you just take off yr cooling line and start the truck & let it flush itself like i always do and you get all of the fluid out , including the torque converter ? 🤔 You do it the hard way .....