Sorry, I missed that bit! Beacon is not cheaper (in terms of gas) than UUPS. For each call, UUPS only requires one SLOAD (storage read) to fetch the implementation address. On the other hand, Beacon requires an SLOAD to get the beacon address and another SLOAD to get the implementation address at the beacon contract, plus the CALL to the beacon. In that regard, UUPS is cheaper than Beacon.
Beacon is better in terms of simultaneous upgrades. You can upgrade multiple proxies in a single tx, whereas in UUPS (or transparent) you need to send one tx per proxy.