This does not mean forcing you to vote for anyone in particular, but it does mean forcing people to turn up and indicate some type of preference - even if that preference is "no one here".
Mandatory voting is common elsewhere [1], and the sell is simple: voting is compulsory for all citizens unless a valid reason is provided (which isn't a high bar for most valid reasons) or a nominal fine is imposed (in Australia - $20 [2]). This fine isn't significant in anyway, it just has to exist because it does two things: asks people how much they seriously don't want to participate in the free thing which ensures their freedom, (2) forces the AEC to look into the matter - they have to try and collect the fine, and in turn ask why someone didn't vote, which means incidents are investigated, and (3) if a lot of people are getting fined the suddenly it's going to very much become a national issue as people make a fuss about it.
It's irrelevant to talk about anything else while substantial parts of the the American voting eligible public do not vote, and no one is responsible for investigating why and ensuring that it was a personal decision and not a problem of lack of access, time or intimidation. You can't run a democracy when the one defining characteristic of a democracy is handled so flippantly.
[1] https://www.aph.gov.au/Parliamentary_Business/Committees/Joi...