HomeKit "this accessory is not responding" after power outage

During the night our power was out due to a bad storm. Today, all of my HomeKit accessories work, including smart lights - but only at the switch.

Both Apple's Home app and the apps for Nanoleaf (A19 and Flood bulbs) and Meross (Flood bulbs) cannot detect the bulbs.

Strange, since some of these were often kept off at the switch and, when on, still responded to the apps and Siri commands. Further, my Nanoleaf LED strips work fine, including via Siri.

There's no electrical damage.

Further, my cable modem and router are working fine and current on firmware updates. Most, if not all, of the bulbs are also current on firmware (though with Nanoleaf, it's a fairly constant barrage of updates).

I've power-cycled through the bulbs numerous times - both short and long durations (avoiding doing a reset; what a massive pain that is esp. since Nanoleaf doesn't have NFC, and scanning the QR code on 14 bulbs is sorta hard as they're in recessed cans in the ceilings.