My first intuition was that this is impossible (at least not with math alone). I have no (proper) proof however.
Ultimately anything could be infinitely parallelized, by brute-forcing the answer itself. If we put the answer safely out of reach for brue forcing, then all that remains is a number of methods of actually calculating it. Those methods can either be arduous but applicable by everyone or fast but requiring some pre-known secret.
For a puzzle that could be solvable by more than one ardous method, it is to be expected that ultimately everyone would be using the fastest one of those - i.e. the author and the public alike, since the methods would be applicable by everyone.
For a puzzle that would be solvable by a fast method requiring some secret, the solution would always be brute-forcable on that secret, and thus have a wide timesrange in which it could be solved, depending on the level of parallelism.
The only way out I see here is to construct a puzzle with more than one arduous method - one of them obviously faster than the other, but only publish one of the methods and use the other one yourself to calculate the time-locked data. This may or may not be possible - but I don't think it's something that can be automated, since it requires creative input, considering how a new kind of puzzle would need to be created for every new piece (or at least every new author) of time-locked data, since otherwise the less-arduous methods would become public knowledge too. (And of course there's always the risk of there being other smart people searching for and eventually discorvering that other less-arduous method, before the desired timespan has elapsed.)