game has been in alpha stage for about 2 years now.
The game is in constant development, there's never been any hide from that, as a game slowly layering on a long term goal always will be. It's a newer model of gaming to get one's head around (or just not play).
As for the question, in world, I can see a reason for it. We're not being charged for ship storage on a station, stations might not want the insurance risk of high valuables being left on ships - you have to lug the small cases of materials around with you. Some will be tiny. But yes, I think now materials are more valuable and can be dropped, there does need to be a module storage next, from a sheer game mechanic front. In the meantime, its how the game is, and by the in-game logic I offer, just something you have to mediate.
Elite is meant to be a long term, real-life immersion. You aren't meant to be rushing collecting every material to go and do big game-stacks for powerful mods. You get a couple of materials requested from a blueprint, and go get an upgrade. If you're very lucky, they'll be a manic effect, but that's a rare. Maybe you'll go back when you chance more of the same materials, but if you live in a world where you can't store unique and untested goods you've picked up around the universe because stations don't want that stuff, you would have to micro-manage how much you want to keep in your escape pod
That is until they do the module upgrade.
