Ugh. I could pick apart your argument like a neural surgeon dissecting a brain but instead I'm going to give you the bullet points because it's late, I'm tired and this is off-topic:
- You can say it was easy all you like but I can guarantee it wasn't. The cost and technical considerations alone would make it a nightmare to just throw a 32 GB flash module into an iPhone gen 1. Just ask RIM. It took them years to figure it out even after the iPhone hit.
- According to Apple's annual report for 2010, they spent about $690,000,000 on marketing and about $1,800,000,000 on R&D. So there goes that theory.
- Creating a new device does not make the preceding version suddenly cease to function. You can still use a gen 1 iPhone today if you so choose. Or are you saying people have to buy new cars and computers every year, too?
Anyway, back to the topic at hand. I did a little digging and found what you are talking about. For those who don't know, basically, when you insert an SD card into your Samsung WP7 phone (and likely any other WP7 phone) it expands the file system onto that SD card. Think of it like running RAID0 in a computer with two hard drives. The SD card you've inserted becomes an extension of the phones own filesystem and, as such, cannot be removed without breaking the filesystem. Now, it's not permanent but it is hard to undo.
The idea behind this is that it gives users a way to expand the total capacity of the device without having to replace the entire device. Though, to change the cards you have to format the entire phone (which is a bit sucky but does make sense from a technical standpoint).
Basically, what this doesn't allow you to do is have five SD cards that you keep photos, music, movies, documents, ect. on that you swap in and out of the device at any time. However, you can still get all your data off your phone by syncing it with your computer so there's not too much of a fuss there.
Personally, I don't think this is much of a deal-breaker because of how I use my phone. It's not a mass media storage device. I have my my laptop for that and soon (hopefully) a tablet. Not to mention it's only a matter of time before someone figures out a work-around. Heck, on the iPhone you can now buy external hard drives that connect wirelessly to the device to stream media.