It's extremely expensive. At $17 or $21 a month which works out to $250 a year you could go to a million other places. For $5 dollars a month wordpress will include a domain and 6 gigs. Hostinger is $2.99 with domain.

Wix doesn't let you move your files.

Good point about the files. Wix is a walled garden.

But cost wise, $20 a month is nothing. The first time they run into a WordPress security, theme, or extension issue, they'll spend more than a year's worth of Wix hosting to hire a dev to fix it.