The answer to why throws in Street Fighter are as they are is very, very simple. If they weren't like that, there would be very little incentive not to simply crouch block all day, given the low block damage and lack of fast overheads in the game. At least with throws that can only be broken on anticipation, you have something to be scared of at close range.
In that respect, throws are designed very well in SF.
"Less effective/stupid" would be more appropriate.
Comparing something good to something better/broken doesn't make it bad. If AE throws were really bad then nobody would ever get thrown by Cammy into unblockable/vortex nonsense but it still happens all the time. Justin Wong probably wouldn't even play Rufus if throws were really bad/too easy to tech.
You can still tech them on reaction and they still do shit damage. Also, the fact alone that they're being used as setups and not as straight up damage should tell you something.