If you're like me, and you wouldn't be if you were properly inoculated, you probably have an editorial point of view on how to create the plural of an acronym and/or just a letter. Good for you.
We won't need to discuss your preference and how, if it varies from mine, it's wrong. Because I'm just conveying the song title as it's actually titled. If you have an opinion take it up with Elle King or her co-writer Dave Bassett.
Song: "Ex's and Oh's"
Artist: Elle King