Case in point:
Japanese, a language that mixes 3 different scripts, one of which is Kanji (Han characters), is taught to everyone in Japanese since pre-school. An excellent Japanese reader can comprehend about 3000 Han characters, incidentally, is also the average number required for a Chinese speaker to read newspaper. Japan's literacy rate has been around 99% for so long that the government has basically stopped reporting that statistic.
In the past 30-40 years, Taiwan, Hong Kong, and Macau, all regions that continue to use the "complex" traditional Han script, has achieved 95+% literacy rate. We don't hear many people in those regions complaining about how hard traditional Han characters are.
As a comparison, India, which teaches Hindi and English in school, both of which much simpler scripts than Han, has achieved an average of 74% literacy rate in the most recent census.
All of the above tells us that the complexity of a language's written script has very little to do with literacy. The dominant factor in improving literacy is the introduction of free primary and secondary education across a region. No other factor even comes close to achieving a high literacy rate.
So stop with this non-sense that the Han script is too complex to teach, learn and use now. 100s of millions of people have done it.
Another point of this article is that the Han script is too rigid, which is not true. The 6 ways of constructing new Han characters has been recognized for millennia, it's just over the dynasties, the rulers have been reluctant to invent new ones to cater to new ideas. It's the people who forces down a way to use it that's rigid.