"Hugh Trevor-Roper is supposed to have said that 'history teaches us nothing except that something will happen', and this applies pretty well to tech: this is so young and so fast-changing an industry that drawing parallels is more misleading than helpful."
Feels about right to me.
Until now, smart phones/tablets have had little in the way of peripherals. Some headsets, keyboards, memory cards, etc., but people seem to be clamoring for certain peripherals above all others. They seem less concerned about CPU types, just like the in Mac and PC world. Key peripherals seem to be camera and some kind of "geekport"/internet of things.
I don't see a need to modularize every part of the phone a la PCs, but to expand the peripherals would help. It might be as simple as adding extra USB ports.
Not sure about this one, seems like the opposite to me. Twenty years ago, PC's were very modular, and it was very common to add/upgrade a sound card, memory, cpu, video card etc. Fast forward to now, and for the most common computing devices (think tablets and smartphones), there is almost zero modularity or upgradability. Even with current PC's (i.e. mostly laptops), it's increasingly limited.
The same trend is apparent in other similar technology. For example with analog TV, people could add a PAL block if their TV was NTSC or SECAM. Upgrading your car used to be significantly easier etc.