It's a fair question, but I'll ask you "what's the alternative?"
We can't plant enough trees. Nor can we always plant them in the most needed places (North, where carbon accumulates). We can't build even public transport (which is still positive emissions). We can't get everyone to go vegan (which still is positive emissions. Even lab meat won't make negative emissions). We can't stop air travel and shipping without significantly affecting people's lives (including their ability to live, as drugs, equipment, and experts aren't all created locally). We can't get everyone to leave their homes and concentrate into cities.
Even if we could do all that, we'd still be positive. Worse, how do we get every country in the world to do the same? It seems infeasible to me. And it doesn't address the problems like that carbon builds up in certain areas that we just can't even plant trees.
But here's the thing. The argument isn't "planting trees vs CC", it is "trees + CC". Actually it's more! It's about using every available method we have at our disposal. There is nothing wrong with burning carbon actually. The issue is burning so much that we are destroying the plant. Destroying the planet is the issue. If we have negative emissions total (and aren't creating carbon hot zones) then who cares how much we emit? As long as it's captured and doesn't damage the planet.
Leaving CC off the table is like telling a bunch of starving children that they can't have hamburgers because some of them might eat too many and get fat. The concern is completely missing the point of the problem.