At 5 Mbps this part supports CAN FD (flexible data-rate) payloads, not just the classic 1 Mbps CAN 2.0 arbitration rate. That matters if the ECU needs to flash firmware over the bus or stream higher-resolution sensor data without saturating the network. The 1/1 driver/receiver count is the usual single-node interface; for multi-drop you still need one transceiver per node.
Supply and temperature — the design-in gate
It will not run on 3.3 V logic alone — the transceiver needs the 5 V rail to drive the differential bus levels per ISO 11898.