it can be a crutch if u use it as a bar instead of doing bar chords. if u never earnt bar chords because its easier just to stick a capo there this is bad and it will limit you.

but if you can do bar chords and u will use them when they are apropriate then there is no reason to also use a capo, it just makes things a lot easier, and can give u access to diiferent voicings. so basically use it but dont depend on it too much