The main problem with tail call optimization is that it's unreliable; small apparently unrelated changes elsewhere in the function, a difference in the compiler command line flags, or a different compiler version, could all make a tail call become a non-tail call. Some languages have proposed explicit markers to force a call to be a tail call (and generate a compilation error if it can't), but I don't think these proposals have been adopted yet.
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A lot of modern programming languages do not do tail call optimization, often citing keeping accurate stack history for debugging as an excuse.
Regardless of how valid the excuse is, for such an obvious and old optimization, it’s very poorly supported.
The main problem with tail call optimization is that it's unreliable; small apparently unrelated changes elsewhere in the function, a difference in the compiler command line flags, or a different compiler version, could all make a tail call become a non-tail call. Some languages have proposed explicit markers to force a call to be a tail call (and generate a compilation error if it can't), but I don't think these proposals have been adopted yet.