It also forces the government to make voting easy.

No it doesn’t. I could easily see Republicans making voting very difficult under such a system, particularly within zip codes that vote for Democrats. This would punish Dem supporters who failed to vote, and would generally make the public hostile to mandatory voting - which would help build public support for the abolition of such mandatory voting

The government is only incentivized to make voting easy if all major parties are loyal to the public. That isn’t the case in the United States