An easily expandable phone isn't always an easily repairable phone. If you need proof, take a look at iFixit's newly completed teardown of the Galaxy S5.
While Samsung's latest flagship gets some kudos for its removable battery and microSD slot, it's considerably tougher to take apart than its GS4 predecessor. You now have to remove the display if you want to replace any of the internals, and the removal process is especially tricky.
From all indications, the GS5 is still easier to fix than some phones we know - it's just not the walk in the park that we saw last year.