I think the cancelling of totp or more likely the lessening influence of TOTP reduced the importance of the chart. You would always see your favourite artist on totp if they had gone up in the charts. Now you can hear and see them on you tube anytime and anywhere.
I remember listening to the charts at dinner time in school on tuesday afternoons with great excitement to hear where in the charts the latest Human League, ABC, or Japan record had got. I imagine only the artists and managers are the only ones that care about this anymore.

Also the fact that you don't need to sell that many units to get into the charts these days. A track from the early 80's that scraped the top 20, would get to No.1 with equivalent sales today, and the population was smaller.

Very true JK,and don't forget changing circumstances,the chart was doomed anyway it that form when the Internet arrived...when was the last time any of us went down the record shop and bought a single,of any format?