A fun champion, with an interesting lore concept and poor execution in fitting her into the meta. If there were ever a better formula for a rework, then we don't know what it is.
Taliyah is a mobile jungle mage, that controls the earth to attack opponents, displace, crowd control, and zone them in team fights, as well as cover vast areas of the map with her ultimate. With such versatility, and such an interesting and fun gameplay concept, she should have been one of the most popular League of Legends champions.
Unfortunately, she is not. This stems from the fact that, though she does all of these things quite well, there is always a champion doing each of those far better than she can. Add to that the fact that her looks are not designed to sell skins in the typical fashion Riot Games use female champions, and we can see the reason she has not been given any love by both the developers and the community.
This is all poised to change with the rework Riot promised her in 2022, alongside Olaf.
And, though we don't know what the changes will entail exactly, we are sure that the new skin she is also promised this year will give us an insight into what they might be. Perhaps, even, the rework itself is planned to be released alongside the skin, making it the second coming of Taliyah to League of Legends.