[2021] Will any planned updates require new world generation?

World generation does never get updated retroactively. A new world is recommended on every major update (10.0 being the next) or update with worldgen changes. On some major updates you might be forced to generate a new world. Keep in mind that Eco is meant for 30 day worlds mainly, even though you can play totally different if you wish to do so.

Definatley not.