>

Elon, is that you?
This is truly an unpopular opinion. If you can afford to build and ship the basic product with the premium feature lurking within, then you can afford to sell it for the basic price.    
This gets to people in a visceral way because you're locking them out of something they own. >

Not always true. Here’s an example. I work for a company building embedded semiconductors. We license the GPU. The cost to build is very cheap. The main cost is the royalty (cost for all the R&D, patents, IP) which is multiple times the actual cost to manufacture it. The company we got the GPU from allows us to not pay the royalty until the customer enables the feature via secure e-fuse. We do the same for additional CPU cores, AI/ML accelerators, etc. So if you buy it, you paid for the HW but you haven’t paid for the R&D/IP/patents/SW. >

That's a great counter example and perfectly reasonable!  
I think the fear I have, and others share, is that once this is the norm, the paywalled on hardware feature will no longer be something subsidized by the premium user, but something gated for pure profit and nothing else. >

Which software are you referring to? >

I think BMW or some other company started charging a subscription for their heated seats >

See, that feels like BS to me. There is no ongoing expense to BMW to keep your heated seats working. There are subscriptions that make sense, like for a software package that is being continually updated and improved, but for something that is just an access unlock? That should be a one-time charge, not a subscription.
What I’m talking about is like the quick-shifter on my KTM motorcycle: I didn’t particularly want it, and certainly didn’t want to pay extra for it. So I didn’t. The fact that it’s there and I can’t use it doesn’t bother me. Meanwhile, people who do want it pay KTM the $900 and BAM now they have a quickshifter. Even better, the KTM dealer doesn’t have to stock two different versions. I didn’t have to deal with the “sorry, we’ve only got the expensive versions in stock…” salesman BS. And here’s the kicker: if, one day, I decide I do want that quickshifter, or if the next owner of the bike does… they just pay the fee and now it’s got a QS! No hardware modifications, running new wire harnesses, any of that stuff. It’s already there.