When you artificially limit what competitors can do on your device it means you can keep your prices high. You don't really have to compete on price when you've already crippled the competition to the point of being much less useful. The other user mentioned specific examples such as the Apple Watch and how it's able to do a lot more compared to competitors like Garmin. I'd even argue products like Tile are another example. Spotify is still fighting with Apple to get some more "fair" competition. Considering how tight margins are in the music world, Apple being able to dodge the 30% Apple tax is a huge bump in their ability to compete.

Overall the list could go on for days, I think you nailed it on the head that it would fit their pattern of behaviour. And they already seem to be following that pattern with their current line of watches and what they can do versus what a non-apple watch can do interaction wise with their phones.