That's easy. Your connectivity tests and mine were different.
You were getting blocked ICMP Echo Requests, which is of course the case because you did not have a pass rule that included ICMP. (ICMP Echo requests are how
ping(8) communicates. ICMP is also helpful for informing users immediately when connections cannot be established, and it usually makes for a better browsing experience for people if they receive an immediate error rather than waiting 30 seconds for a TCP timeout. It's a key Internet protocol.)
I was not testing with ping. I was testing with the TCP protocol, as I wanted to test state establishment and stateful functions.
As this was just a lab experiment, I was using
nc(1) as my testing tool. On the "Internet server" I used the options -l and -k, for example:
$ nc -kl 1234
To connect to this "server" (at lab IP address 99.99.99.100) from platforms on the WLAN and LAN networks, I used:
$ nc 99.99.99.100 1234