Octavean I run both TrueNAS and Proxmox, both are good, really depends what you want to do. TrueNAS Scale, runs under Linux, as opposed to FreeNAS/TrueNAS Core. Hardware-wise, your past issues would be gone. The UI has been revamped as well.
In the TrueNAS vs. Proxmox "debate" my view is, TrueNAS is NAS first, apps or VM seconds. Apps are ok, but meh. VMs work fine (KVM hypervisor for both systems) but the UI is lacking and the configuration not so intuitive.
Promox has a UI that is quite familiar to anyone that used VMWare ESX/ESXi. I would say it's an industry-standard UI at this point. Everything is well organised, but it's a VM "only" system. If you want a NAS, or containers (outside of LXC) you have to run that in a VM, which might be better or worst for some.
I personally run my critical stuff on TrueNAS and primarily use Proxmox to try out stuff. I have seen people run everything in Proxmox and virtualize TrueNAS, there are no right or wrong approach. In both cases, they support ZFS. I would argue you get more ZFS finetuning in TrueNAS, if that's something you are after (most people aren't).
