Let's run the numbers. $800 is the ceiling as this is the cost of the internal Apple Option for 2 tb. Same arguements apply for 1 tb but the cost savings will be less. Economy (or in this case not) of scale.
I typically buy the low storage options so I don't feel bad about upgrading soon. So in this case 256 gb. Cheap. I use my laptops for dual purposes, travel or at home convenience. Two different applications, two different solutions, but I start from the same base configuration, on my internal drive I load up my productivity apps. I do use Apple photo which can be a hog, but keep my pics in the cloud (easy to select apple option). And that's it.
For work I am dealing mostly with smaller files (word processing, spreadsheets.) And so I keep all my work files on DropBox (a cloud option) that allows me to keep them synced with my work desktop (stored locally) and accessed on my lap top via the cloud. I can keep what I am currently working on downloaded on my laptop, but the bulk (700 Gb) in the cloud. Dropbox makes it really easy to determine what stays in the cloud or on my device. It works well for me because I use 3 separate devices (work desktop, home desktop, and laptop for travel). It does cost, about $120 a year for 2 Tb but the convenience is amazing, and built in backup. Now when I travel for work or play, I do like to carry some entertainment with me. In this case a 2tb Samsung T5 for games, movies, etc. Cost $230 (currently). It is about 3-4 times slower than built in Apple option, but honestly its super fast versus super duper fast and in most casual applications that's like a blink versus half a blink. Not important.
so let's add this up. Work use. $230 Samsung 2Tb T5 + 2Tb dropbox $120 a year.. essentially the break even is 5 years versus just coughing up the $800 to begin with. Trade offs? More effort. Something more to carry. But it does have backup built in via dropbox. For me it works well to go with the low cost option (256 built in storage) as I tend to upgrade every 2 years.
let's talk home use. More options. Dropbox is less handy because I tend to use larger files at home (video editing, photos, games, etc.). I would think Apple cloud is the same. Large files, slow sync speed, lots of blinks. So yes, the $230 Samsung comes to mind, but then the slower speeds might be an issue (isn't for me). I recently played around with a Raid 0 NVMe enclosure (2, 1tb sticks).. total cost was about $390. It is still a tad slower (75% of) than internal speeds, but it also provides 60 watt of power so it acts as a power supply for my laptop as well. I do worry about reliability. But clearly $230 or $390 is less than $800 with very little convenience difference for a stay at home machine.
Thunderbolt 3 Two-Slot M.2 NVMe SSD Enclosure Support Thunderbolt 2 Compatible with New M1 CPU
www.amazon.com
So clearly there is an Apple tax for convenience. It may sound like a lot, but spread out over 5 years is it? I think the answer to you question has to include how much time between upgrades. Resale value is not a great place to recoup costs on storage, so it works for me to get the low storage options. But if I was going to keep my machine for 5 or more years, I might just pay it up front with Apple.
But then, you mocked me for my appreciation of the AirPod Max, so I suspect our value analysis differs.
