Also, a more experienced user may already is used to set up firewall rules from some saved rules, the majority of users still forget to secure the system after the initial installation.
What if you are a laptop user jumping into different networks regularly; Having applications installed that open ports on your network interfaces ? What if you are a desktop user having devices in your network that cannot be trusted ?
Imho, having a firewall installed/enabled (blocking incoming traffic by default) makes sense.
Although I already see forum threads coming like samba server not working, can not connect to ssh on my machine