You definitely don't need 10Gig for security cameras, my Unifi 4K cameras only link at 100Mbit and use about 8-15Mbit depending on the encoding.
I have a Chinese equivalent of something that Reolink offers (some no name brand that I'm sure is just importing Chinese stuff and put a basic firmware on it) that runs 4 cameras and the NVR has 8 ports on it, support only 100mbps if I remember right. Even with 16 cameras with a GOOD NVR from a reputable US brand it probably won't exceed 2.5gbps. The cost of running a Cisco switch would likely be enough to split the vlan out into a dedicated dumb physical switch away from the non security camera stuff with some dumb PoE injector that won't burn up the switch. There is no better security than physical isolation.