I'm not serious, but I'd say that there's little actual use of TDT because it requires us to solve the difficult problem of finding the right causal and logical structure of the problem - this can be handwaved in by the user, but doing that feels awkward. Folk-UDT ("just execute the best strategy") is sufficient for most purposes, both in application and in e.g. trying to understand logical uncertainty.

On the other hand, using causal structure is what lets us consider hypotheticals properly - so TDT will not have some issues that typical-UDT does with hypotheticals about its own actions. On the mutant third hand, TDT's solution of adding logical nodes to the causal structure might just be a simplification of something deeper, so it's not like we (us non-serious decision-theory dilettantes) should put all our eggs in one basket.