Firstly, make sure you have a definitive definition of the word dimension.
Then look at empirical evidence.
So, a dimension is an abstract model we use to calibrate and index an aspect of reality.
For exame, Temperature is the dimension of heat. Temperature is abstract, heat is real.
The only empirical evidence of ‘time passing’ is change. We use standard units (years, days hours etc) to calibrate change.
Time is the dimension of change. Time is to change what temperature is to heat.
So, I can’t see anyway that time cannot be considered a dimension. It is (in this context) a calibration and measurement framework, built on standard units. Just look at your clock. Time is a dimension.