Asana can't be the central hub for communication.
Part of the purpose of a CRM is not just storing contact records (that's the most bare-bones use-case of a CRM) but rather to be a central hub of communication across your company.
You email a customer, and someone else on your team emails that same customer. How do you know this happened? You don't when using Asana as a CRM. So customers may get 2-3 emails from different team members and it's a mess.
A proper CRM is going to ingest emails automatically, count the number of interactions you've had with someone, and nudge you when you're not doing a good job at staying on top of leads. Asana as a CRM on the other hand will not be able to handle this type of communication tracking.
Asana is one of the best project management tools - but definitely not the best CRM software.
