If you see the error message "Sorry, you can only add 3 paths right now" - don't despair!
This is a soft limit set by Zapier. The reason is, a zap can't have more than 100 steps total, and if people add too many paths, it's likely you'd hit this limit pretty quickly.
If you have good reason to add more than 3 paths to your zap, then just reach out to Zapier support, explain how many path branches you need and what your zap does. If it makes sense to increase your path limit, they are very likely to agree - just remember that overall step limit!
You can open a ticket here.