Yes.
There has been a continuous increase for 5 years, totaling up to a 13% rise from 2017-2022.
There are 14.9 million individual investors as of the end of 2022, which is around 12% of the population.

(Note1: blue bars for number of individual shareholders (left axis), gray line for rate of change (right axis))
(Note2: assumed that individual investors = indivicual shareholders)
By the way, yes, noticed the misleading handling of axis in the graph. Hope for improvements from the JSDA.