I was excited to check out 5TD because it's an OSR that uses 5E as its core. I'm generally not a fan of OSR clones because they are usually billed as old-school and streamlined but still use archaic and necessarily complex systems because they are nostalgic sacred cows.
But I digress...
But as others have said, 5TD feels incomplete or simply a set of house rules. I would certainly give it a try though, specifically because it is based on 5E. There's a lot of cool ideas too: I like the streamlined classes, equipment rules (especially supply and repair), and the monster creation rules.
It still feels like a lot of the work is going to be on the DM to fill in the blanks, but I guess that's one of the points of OSR gaming. Overall 5TD is intriguing but there's something missing I can't put my finger on.