Ping only works one way

I have a debian 10 server connected to a network via static IP. The network consists of some workstations that are local with respect to the server (they're connected to the same switch) and some workstations that are remote (connected to a fiber optic network). The other workstations are windows-based.
It looks something like this:

server: 172.16.10.23
workstation 1: 172.16.10.21
workstation 2: 172.16.10.22
...

remote workstation 1: 172.16.122.11
remote workstation 2: 172.16.122.12
...

The problem is:
- I can ping the server from any workstation
- I can ping any workstation (including remote) from the server
- I can ping any workstation from any remote workstation (and vice versa)
- I cannot ping the server from any remote workstation

I have excluded:
- the switch blocking ping requests (although it's managed, it's set up to let any traffic on the network)
- IPv6 is disabled on the server
- hardware (swapped different NICs)
- windows related stuff (disabled firewall, uninstalled antivirus etc)

Interfaces:

Code:# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

allow-hotplug enp1s8
iface enp1s8 inet static
address 172.16.30.23
netmask 255.255.0.0
network 172.16.30.0
broadcast 172.16.30.255
up ip route add 172.16.30.0/24 dev enp1s8 table enp1s8
up ip route add default via 172.16.30.254 dev enp1s8 table enp1s8
up ip rule add from 172.16.30.23/32 table enp1s8
up ip rule add to 172.16.30.23/32 table enp1s8

allow-hotplug enp1s0
iface enp1s0 inet static
address 172.16.10.23
netmask 255.255.0.0
network 172.16.10.0
broadcast 172.16.10.255
gateway 172.16.10.254
up ip route add 172.16.10.0/24 dev enp1s0 table enp1s0
up ip route add default via 172.16.10.254 dev enp1s0 table enp1s0
up ip rule add from 172.16.10.23/32 table enp1s0
up ip rule add to 172.16.10.23/32 table enp1s0(There's actually two NICs, two separate networks, but the other one works fine)

Routing table:
Code:#
# reserved values
#
255 local
254 main
253 default
0 unspec
#
# local
#
#1 inr.ruhep
1 enp1s8
2 enp1s0I'm thinking maybe there's an issue with the server, although as far as I know debian doesn't come with an active firewall.