Frequent dropouts for some but not all players

Most often as a "Internal Exception: java.net.SocketException: Connection reset

I'm trying to reduce the frequency of players being disconnected/ Improve the reliability of my server.
The dropouts seem to happen to some players frequently or at the same time, and some players are not having any issues at all.
Sometimes players will be fine all day and then drop, rejoining works but then disconnection happens again 5-10 minutes later.

Specs and I think relevant info of the host machine:

- OS: Debian 12 with CasaOS for interface and Crafty Controller
- Playit.gg as a proxy
- CPU: Ryzen 5 5600g
- Ram: 32GB
- NVME SSD for the boot and server storage
- Mod pack: Integrated MC
- Up to 25 active players, but happens with low or high players active
- 400mbps max upload speed

Startup commands (Any advice on this also greatly appreciated, mostly learning as I go)

"/usr/lib/jvm/java-21-openjdk-amd64/bin/java" -Xms16g -Xmx16g -XX:+UnlockExperimentalVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+AlwaysActAsServerClassMachine -XX:+AlwaysPreTouch -XX:+DisableExplicitGC -XX:NmethodSweepActivity=1 -XX:ReservedCodeCacheSize=400M -XX:NonNMethodCodeHeapSize=12M -XX:ProfiledCodeHeapSize=194M -XX:NonProfiledCodeHeapSize=194M -XX:-DontCompileHugeMethods -XX:MaxNodeLimit=240000 -XX:NodeLimitFudgeFactor=8000 -XX:+UseVectorCmov -XX:+PerfDisableSharedMem -XX:+UseFastUnorderedTimeStamps -XX:+UseCriticalJavaThreadPriority -XX:ThreadPriorityPolicy=1 -XX:+UseZGC -XX:+ZGenerational -XX:+UseStringDeduplication -XX:AllocatePrefetchStyle=1 -XX:-ZProactive -jar server.jar nogui

Server.properties currently is

allow-flight=true
allow-nether=true
broadcast-console-to-ops=true
broadcast-rcon-to-ops=true
difficulty=normal
enable-command-block=false
enable-jmx-monitoring=false
enable-query=false
enable-rcon=false
enable-status=true
enforce-secure-profile=true
enforce-whitelist=true
entity-broadcast-range-percentage=75
force-gamemode=false
function-permission-level=2
gamemode=survival
generate-structures=true
generator-settings={}
hardcore=false
hide-online-players=false
initial-disabled-packs=
initial-enabled-packs=vanilla
level-name=world 3
level-seed=8928663378103035750
level-type=bclib\:normal
max-chained-neighbor-updates=1000000
max-players=30
max-tick-time=60000
max-world-size=16000
motd=Austubers Minecraft
network-compression-threshold=128
online-mode=true
op-permission-level=4
player-idle-timeout=0
prevent-proxy-connections=false
pvp=true
query.port=25565
rate-limit=0
rcon.password=
rcon.port=25575
require-resource-pack=false
resource-pack=
resource-pack-prompt=
resource-pack-sha1=
server-ip=
server-port=25565
simulation-distance=4
spawn-animals=true
spawn-monsters=true
spawn-npcs=true
spawn-protection=0
sync-chunk-writes=false
text-filtering-config=
use-native-transport=true
view-distance=8
white-list=true

What I have tried:

Previously resetting the world map helped, but this does seem to be something that over time gets worse.
network-compression-threshold seemed to have a noticeable effect on already affected players (Raising the amount made it worse)
Getting members of my community to try ipconfig /flushdns, change their default dns and review their firewall settings
Ongoing tweaks to the startup commands to lighten network and cpu load
Toms simple storage usage being cut down (I'd hard disable it but I'm currently trying to read into how to do that)
Server Core configs configured

And specifically:

Is there any changes I can make in my setup to improve network and performance stability, performance being secondary to maintaining higher player count at peak hours.
Is there anything I can suggest members try on their end to resolve the connection issues?