Bluesky was an EEE operation. Meant to kill federation by capturing users then forcing an instance monopoly. That’s why it is federated on paper only. In practice no engineering was done to make it actually federated at all. Now they’re far behind the Activity pub and mastodon, and the rest of the fediverse despite having much more investment.
It’s usually the electronic drivers. They overoverheat and degrade. Most burned LED bulbs still have working LEDs and just need to replace some component of the driver board.