I owned 4 laptops, got my first one in 2008. For all of them I have upgraded RAM and disks immediately after the purchase. For some of them upgraded SSDs after couple years of use: both speed and cost per GB are quickly improving over time for them.
A soldered SSD is especially bad because broken laptop = lost data. I never broke a laptop but I think that was just my luck. When it will happen, I want to be able to recover data from the computer.
About the 3.5mm audio jack, bluetooth audio is not good enough for music, it simply doesn’t have the bandwidth. Uncompressed 16 bit / 48 kHz stereo exceeds 1.5 mbit/second, while Bluetooth audio has throughput of 300-400 kbit/second and uses some lossy codecs on the air.