It wasn’t Hue.
Osram made the decision to use the ZLL zigbee profile in Europe and the ZHA zigbee profile in the US. The Hue Bridge was originally a ZLL device in both regions. So Osram bulbs with a Z LL profile worked fine with the Hue Bridge. Osram bulbs with a ZHA profile did not. There was much discussion in this forum about it at the time.
Since that time, the Hue Bridge was updated to zigbee 3.0, but the Osram devices were not. In fact, Osram gives that as one of the reasons why they are discontinuing their cloud service: they say their devices use the older profiles and are now out of date.
Furthermore the implemented ZigBee® standard is not state of the art anymore (ZigBee® Light Link and ZigBee® Home Automation instead of ZigBee® 3.0) which makes it more and more difficult to ensure compatibility to other smart home systems.
There was a very brief period, about four months, when Hue decided to lock out third party bulbs like Ikea A few years ago, but they withdrew that after customer complaints and since that time most bulbs that meets the zigbee 3.0 standard will work with The current generation. But that was a different issue.
Hue didn’t decide to “lock out” Osram bulbs in the US any more than smartthings decided to “lock out“ the Hue Tap device. They just use incompatible zigbee profiles.
Submitted with respect.