Apple announced that it was discontinuing the original HomePod back in March, with Apple focusing its efforts on HomePod mini. The product has been listed as available ‘while supplies last’ since that time.
The space gray model sold out within a couple days of the announcement. The white model remained available to buy (price unchanged) up until today.
The HomePod product page on the online store has not yet been removed. This suggests there may be some remaining stock still to work through. (When the iMac Pro was discontinued, all references to the model were removed from the online shop within a few hours of going out of stock.)
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