This is the old “why buy a prebuilt PC when you can DIY for less”. Which is true, but completely misses the point that may people will happily pay to 1) not have to build it, and 2) have e2e warranty, and 3) have someone else do the software setup.

We can debate if it’s the most efficient use of money for a technical person, but it’s indisputable that many people get enough value to pay for the prebuilt.