The problem with TA is that it's been stuck in a loop of not getting the correct design implemented from the start.
Originally, TA was supposed to be public and available for all, but the publication has been delayed because Deadcode's plan was to make encrypted TA replays switch places with public replays. So you could freely alter the contents of the decrypted replay for TA purposes, but altering regular replays would not be possible. This was the plan but currently we're still stuck in a state where this format change has not happened, and therefore the build has not been made publicly available.
I've seen a new implementation of tool-assisted recently. The problem is that it suffers from the same design problem, where TA replays are encrypted, when it should be the other way around. The only solution to that unfortunately is waiting for proper support for the new format(s) in the base game.