A Tor exit node is the last relay in a Tor circuit — the machine that makes the request to the destination on the user's behalf, and therefore the address a server sees. The Tor Project publishes the list of them, so this is one of the few network facts that is exact rather than inferred.
What Spaw answers
is_tor is the flag, and it feeds is_anonymous along with is_vpn and is_relay. The risk score carries +70, the heaviest of the anonymity signals: a VPN is +30 and Apple's iCloud Private Relay is +10.
The gap between those three numbers is the whole judgement. Tor conceals origin deliberately and is rare in ordinary consumer traffic; a commercial VPN is a privacy product millions of people leave switched on; Private Relay is on by default for iCloud+ subscribers and says almost nothing about intent.
What it does not mean
Tor is used by people who need it. Treating +70 as a block is a policy decision, not a reading of the data, and the guide beside this entry argues for a step-up rather than a refusal. Nothing in the answer identifies the person behind the circuit — that is the point of the circuit.