The verdict

CPU
Lenovo ThinkCentre M715q Tiny has 1x the CPU throughput (7,794 vs 7,735 PassMark).
Idle power
Dell OptiPlex 5060 Micro idles lower (9W vs 11W) - cheaper to run 24/7.
RAM ceiling
Dell OptiPlex 5060 Micro takes more RAM (64GB vs 32GB).

Which wins for each job

Job Dell OptiPlex 5060 Micro Lenovo ThinkCentre M715q Tiny
Plex / Jellyfin ~3 streams ~3 streams
Frigate NVR ~4 cameras win add a detector
Proxmox / VMs 7,735 PassMark 7,794 PassMark win
Firewall / router 1 NICs 1 NICs
Local AI / LLM no slot no slot

Approximate - capacity estimates from curated specs, the same logic as the recommender. Verify against your exact setup. Prices move; check the retailer.

Full specs

Spec Dell OptiPlex 5060 Micro Lenovo ThinkCentre M715q Tiny
Price (list) $95 $85
CPU Intel Core i5-8500T AMD Ryzen 5 PRO 2400GE
Cores / threads 6 4
PassMark 7,735 7,794
iGPU Intel UHD 630 Radeon Vega 11
NICs 1 1
NIC model Intel I219-V Realtek RTL8111
RAM max (GB) 64 32
M.2 free 0 0
PCIe slot none none
Idle (W) 9 11
TDP (W) 35 35