Technetium's absence from the Earth is not an absence from the universe. In 1952 Paul Merrill, observing S-type red giant stars at Mount Wilson, identified technetium absorption lines in their spectra.
The significance is hard to overstate. Technetium's longest-lived isotopes survive a few million years, which is nothing at all on a stellar timescale. Its presence in the atmosphere of a star means it is being made there, now, and dredged to the surface. Before Merrill, the idea that stars manufacture the heavy elements was a theory; after him it had direct observational support, and the great synthesis papers on stellar nucleosynthesis followed within a few years.
The element's terrestrial career is medical, and it is enormous. Technetium-99m, a metastable nuclear state identified by Emilio Segre and Glenn Seaborg in 1938, decays by emitting a single gamma ray of convenient energy, with a half-life of about six hours: long enough to image a patient, short enough to clear quickly afterwards. It can be attached to a wide range of carrier molecules that concentrate in bone, heart muscle, thyroid, kidney or tumour tissue.
It is supplied by a device called a technetium generator, in which molybdenum-99 decays into technetium-99m and the product is washed out with saline as required, so that a hospital can draw fresh doses for a week from a single delivery. Technetium-99m is used in tens of millions of diagnostic scans a year worldwide, the great majority of all nuclear medicine procedures.
An element that does not occur naturally on this planet, was announced only in 1937 and was disputed for a century before that, is now among the most administered radioactive substances in medicine. Nothing traditional attaches to it, and nothing could.