Bandwidth has improved, i.e., internet speeds have improved. But the internet is not the web.
The amount of data websites try to make users transfer, e.g., through browsers that auto-load resources and run Javascript, has also increased. The number of websites using "simple HTML" has decreased, even though it makes the web faster. As such, for the web user, the speed of the web (cf. internet speed) has not improved. At best it has only stayed the same.
Thanks to increased internet speeds more data can be transferred in less time. But if the amount of data is increased instead of being held constant, e.g., simple HTML is no longer "good enough", then over time the user may not notice any speed improvement when using the web. The amount of data being transferred over the web today attributable to marketing, advertising, tracking and telemetry, and the number of DNS lookups to support those connections, has increased substantially.
When "tech" companies purport to work to "make the web faster" their strategy is never to reduce the practices that make the web slower, like advertising. In some cases they are working to allow more such traffic, without affecting speed too much so as to alert the user. Or to allow routing website traffic through their own servers, e.g., AMP.
Transferring the data required for 1990s websites over today's internet would make the 1990s web noticeably faster. Unfortunately, today's websites and "ad tech" are substantially more resource hungry, mainly for the benefit of generating revenue for "tech" company intermediaries. The user foots the bill for the increased resource usage.