Because “life hacks” and “productivity tips” are next to “viagra” and listicles when it comes to “stuff I reflexively delete from in my inbox”. Anyway, “schemes” evokes the snake-oil sheen that productivity tricks have, whether you are selling them to others or to yourself. This is the correct attitude.
The corollary of this is that it gets much, much harder to winnow out activities over time. Anything I remove from the Jenga stack of my day disturbs the whole tower.
And that means that undertaking new things, speculative things that have no proven value to any of the domains where I work (let alone all of them) has gotten progressively harder, even as I’ve grown more productive. Optimization is a form of calcification.
However, one should still avoid clickbait.
Time management tools
See time management.