Personally, I get the impression entry-level fitness bands have reached a natural limit in terms of the data they collect, whereby the data is sufficient in sco

Personally, I get the impression entry-level fitness bands have reached a natural limit in terms of the data they collect, whereby the data is sufficient in scope and accuracy for the average person (trying to lose weight, train for a 5k/10k etc). A device that covers this criteria is very low cost so big brands don't want to bother. You can pick up fitness bands on Amazon for less than £30 which work for most use cases. On the other end, advanced fitness bands are somewhat converging on smartwatches in both their features (sleep tracking, GPS, music control and phone notifications, maps) and price point, because this is the only way to make something big brands consider worth selling. Heck, I run over 150km a week, and I wear one of the cheapest Garmin watches available, and I know many people who run a decent amount (50 to 100+km per week) who are in the same situation. There's no major updates my watch needs.