My work involves writing software for big routers and switches used by ISPs, data centers, campuses, etc. and I can guarantee you that a router will 100% switch/route your exotic packets with an unknown L4 protocol number. It literally does not care about anything past the IP header.
There are a few things I can think of that may have led to your experience, one of them is NAT. Well, NAT just sucks. It is the reason why I want IPv4 to die. Just getting rid of NAT will be worth the pain of switching to IPv6.
My work involves writing software for big routers and switches used by ISPs, data centers, campuses, etc. and I can guarantee you that a router will 100% switch/route your exotic packets with an unknown L4 protocol number. It literally does not care about anything past the IP header.
There are a few things I can think of that may have led to your experience, one of them is NAT. Well, NAT just sucks. It is the reason why I want IPv4 to die. Just getting rid of NAT will be worth the pain of switching to IPv6.
PS - IPv6 NAT is just downright stupid.