Know who else argues about this? No one. The rest of the world takes these things ("reforms") for granted.
And it's no coincidence that the rest of the world, the part that votes, has a WAY higher average turnout rate than we do.
So it comes down to WHO wants fewer people participating in the electoral process, and WHY they want that.
Why do Democrats see high voter turnout as an inherently good thing?
Let me ask it another way - if there was some means of ensuring that only the wisest people could vote (not saying there is, it's just a hypothetical), would you support that? Why not?