While I do agree with Matt on the impossibility of playing all the games that are published in a year, that problem is as big now as it was 10 years ago. Once there's more than 100 games published, playing them all is hopeless. And nobody did 10 years ago. All the lists back then were a sham too.
I guess if you really wanted to do a GOTY, there's several ways, most of which require selection and hard work. If you wanted to do a best of for 2018, you should have started a year ago and hunted for it. Pick the games of good designers well in advance, and keep an ear out for games in the outfield. There's a lot of games coming out, but you can dismiss 90% on first sight and another bunch on a 30 minute read through.
Limiting your scope (I would have loved a list on the best Ameritrash games of 2018) makes it a lot easier. And most reviewers do this implicitly by crossing of kids games and wargames wholesale. But even then it's still a lot of work, quite possibly undoable for a part time reviewer. And you would have to give up playing older games, which would suck out the fun of the whole excercise.
You could wait with the list until the end of 2019 and let others do a lot of the selection for you. Actually, to do a GOTY2013 now is probably not a bad idea. The hype has gone and it should be possible to say which ones have stood the test of time.
And all that only if you think a GOTY is a good idea in the first place.