The verdict
If you manage many projects, want tasks, docs and hours in one place and have someone to own the setup, pick ClickUp. If you want a quick personal list that a small team can also share, pick Todoist.
Both have a free plan, so test with a real week of work. I ran ClickUp at my own agency for about a year. The visibility was a real gain, but some colleagues found it too much. Todoist stays simple, and once you need time tracking, resource planning or detailed reporting you will feel that limit. My view of Todoist comes from desk research rather than recent use.