I already know it's impossible to have separate places for SMS and emails, but does anyone know why they did it? Do you think it's possible that it can be fixed in an update?

you can seperate you emails from you sms in ver .107 you will have 2 diff icons you have to go into your message settings and select seperate in general options and scroll down

^^x2. Correct. The option was available before OS 4.2.1.107, check your version before upgrading, could be there already.

Any 4.2.1 apps version should be able to separate