Here's Apple's official statement provided to TechCrunch.
HomePod mini has been a hit since its debut last fall, offering customers amazing sound, an intelligent assistant, and smart home control all for just $99. We are focusing our efforts on HomePod mini. We are discontinuing the original HomePod, it will continue to be available while supplies last through the Apple Online Store, Apple Retail Stores, and Apple Authorized Resellers. Apple will provide HomePod customers with software updates and service and support through Apple Care.
Apple has already sold out of the Space Gray HomePod but you may still be able to find the speaker at third party retailers.
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