With that fast SSD, do you notice paging in Xcode? Would it be worth the extra $300 or however much Apple asks for extra 8GB of ram in the US store?

yes, you notice paging, even with 'fast' SSD.

or perhaps it's not 'paging', and just dumb luck I hit and see beachballs on multiple new higher-end macbook pros regularly.

It's not normally paging, but thermal throttling which involves the machine appearing to 'spin' but it's actually just the kernel keeping the cycles to itself, which typically give you beachballs as a side-effect.

And one tip is to use the right hand side USBC ports for charging, not the left hand ones as for some reason or other they tend to cause the machine to heat up more...

the right hand ones are the only ones that can drive external monitors (on mine anyway). I feel like I'm the only one that has this - I had a MBP 2019 - first batch - and I thought I'd read that one side was different than the other re: power. Power works on both sides, but monitors won't run from the left usb-c ports. but it's not documented anywhere. :/

thx for tip.

I just tried plugging my monitor into a right hand socket on my 2019 MBP, and it worked fine for me.

On my machine it is true that charging on the right is better. Charging on the left spins up the fan.

Just a thought, but maybe everyone should be appalled at that extra $300. And the lack of upgradability on a Pro machine, especially.

You're talking to Apple customers. Being gouged is a way of life for them.