They could have easily made the RAM and Storage user serviceable/upgradeable

Nope, they couldn’t have, since the A18 pro chipset doesn’t support modular memory at all, of expanding it past 8gb. It’s a phone chip after all. There’s also the fact that Apple has equipped all their devices with unified memory, which, if they even managed to make it upgradable, all chips would need to support massive memory bus widths to have the same or similar bandwidth (requiring more modules), would need proprietary modules or at least rare modules like SOCAMM, and would reduce the space inside the chassis for anything else, like battery, modular ports, etc.

Sure, I hate Apple’s antics in terms of lack of right to repair, but frankly they produce arm based computers, where have you ever seen an arm based laptop or mini pc with modular RAM? I’m sure some exist but they’re likely too obscure for me to have heard of (although I have heard of System76’s Thelio Astra, although again they are a bit obscure outside Linux circles.)

Edit: forgot to add, but yeah soldered storage is really inexcusable.

Not allowing a 1TB option certainly is a choice, and one that can be criticized. But I don’t think it’s fair to say they could have “easily” made the RAM upgrade (certainly not user upgradable) at that price point. It uses the A series because they make billions of them, and ram has not been upgradable in them.