Last time I checked there was no equivalent to these, or any sort of actual tiling manager in MacOS; is this still the case? (For anyone to answer, if you know.)
I use Yabai and it works very well. Similar to i3 in how it tiles, and quite customizable.
Amethyst is pretty good
I think that was replaced by Rectangle.
Rectangle and Amethyst are both great, but only Amethyst will auto-tile your windows as you open them, like i3. Rectangle just exposes keybindings to resize the selected window.