Dummy interface is not reachable from other system through ping

I connected two Debian 10 systems with a direct link. On one of them I defined a dummy interface and on the other I gave a static route to access it. I see the traffic from the sender on the interface, but I don't see the traffic on the opposite system, and no response is received. Is it possible that the traffic was dropped by the opposite system? sudo ip link add lo1 type dummy sudo ip link set dev lo1 up sudo ip addr add 13.13.13.13/32 dev lo1

pc2~$ ip addr show lo1
   63: lo1:  mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
    link/ether ae:e2:d8:95:2b:ae brd ff:ff:ff:ff:ff:ff
    inet 13.13.13.13/32 brd 13.13.13.13 scope global lo1
       valid_lft forever preferred_lft forever
    inet6 fe80::ace2:d8ff:fe95:2bae/64 scope link 
       valid_lft forever preferred_lft forever


pc2~$ sudo sysctl -p
sysctl: cannot stat /proc/sys/net/ipv4/tcp_syncookies: No such file or directory
net.ipv4.conf.all.log_martians = 1
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.icmp_echo_ignore_broadcasts = 1
kernel.printk = 1 4 1 7
net.ipv4.conf.all.rp_filter = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2

and another system:

sudo ip route add 13.13.13.13/32 via 20.20.20.2

pc1~$ ip addr show port25
31: port25:  mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 04:f8:f8:76:53:59 brd ff:ff:ff:ff:ff:ff
    inet 20.20.20.1/24 brd 20.20.20.255 scope global port25
       valid_lft forever preferred_lft forever
    inet6 fe80::6f8:f8ff:fe76:5359/64 scope link 
       valid_lft forever preferred_lft forever

pc1(20.20.20.1)-------(20.20.20.2)pc2(lo2:13.13.13.13/32)

pc1~$ sudo tcpdump -ni port25 icmp

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on port25, link-type EN10MB (Ethernet), snapshot length 262144 bytes




22:54:42.098033 IP 20.20.20.1 > 13.13.13.13: ICMP echo request, id 3321, seq 0, length 64
22:54:43.107142 IP 20.20.20.1 > 13.13.13.13: ICMP echo request, id 3321, seq 1, length 64
22:54:44.117137 IP 20.20.20.1 > 13.13.13.13: ICMP echo request, id 3321, seq 2, length 64
22:54:45.127138 IP 20.20.20.1 > 13.13.13.13: ICMP echo request, id 3321, seq 3, length 64
22:54:46.137143 IP 20.20.20.1 > 13.13.13.13: ICMP echo request, id 3321, seq 4, length 64

pc2:~$ sudo tcpdump -ni port25 icmp
Password: 
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on port25, link-type EN10MB (Ethernet), snapshot length 262144 bytes

pc1~$ ip route
default nhid 16 via 192.168.60.2 dev enp0 proto 196 metric 20 
13.13.13.13 nhid 79 via 20.20.20.2 dev port25 proto 196 metric 20 
20.20.20.0/24 dev port25 proto kernel scope link src 20.20.20.1 
50.50.60.60 nhid 16 via 192.168.60.2 dev enp0 proto 196 metric 20 
192.168.60.0/24 dev enp0 proto kernel scope link src 192.168.60.75 
192.168.121.0/24 dev port2 proto kernel scope link src 192.168.121.37 linkdown

pc2~$ ip route
default nhid 26 via 192.168.60.2 dev enp0 proto 196 metric 20 
20.20.20.0/24 dev port25 proto kernel scope link src 20.20.20.2 
192.168.22.0/24 dev port1 proto kernel scope link src 192.168.22.156 
192.168.60.0/24 dev enp0 proto kernel scope link src 192.168.60.76 
zharf-switch:~$