The Michelson-Morely experiment was not a failure.
It successfully and accurately measured a null result for an effect that was previously thought of as essential to ‘modern’ physics. The equipment was enhanced to cover the predicted result when the previous version lacked sufficient accuracy. So the improvements didn’t tie the Luminiferous Ether to an ever smaller constraint as the search for the Biggs-Hoson.It showed that with sufficient detail the Luminiferous Ether was built on dreams, not science.
The concept of a null result being a failure is a failure of perception. One that colors much too much of science, physics included.