I've been thinking a 3ATB formation (3-5-2, 3-4-3, 3-4-2-1, whatever) should be seriously explored going forward as it is. We really have not looked as good in a 4-3-3 especially against better competition. Our D was seriously exposed against Switzerland and the Honduras Nations League match was not any better. Against Mexico Gregg chose to go with 3 CB (and one was even Tim frickin Ream). Besides the D looking exposed in the 4-3-3, it just seemed too congested in the midfield with Dest cutting inside and both wingers dropping back. The huge asterisk of course is that Tyler Adams did not feature much in those games. Most of the top guys for the USMNT play in 3ATB formations- Adams, McKennie, Richards, Brooks, Dest. I can't pretend to know what Genk play. Fulham alternated between 3 and 4 defenders, but Robinson played almost exclusively when they went with 3 ATB and sat when Parker decided to go with 4 defenders.
None of that really matters in the Gold Cup. The roster has been selected and it's too late to make any changes. We seem to be too thin at CB to make a 3-5-2 work and too thin at wingers (assuming Arriola has a serious injury) to make a 4-3-3 work. I'm not too optimistic about our chances once we get to the knockout stages. I'd love to be wrong though.