Correct, but I'll go so far as to say it never ever works. "Planned obsolescence" may have happened once in a great while throughout history, but as a sensible omnipresent business strategy it's a myth and always has been. What I believe people confuse it for is the decision making that accompanies the cost of creating the product of various qualities. In other words, no one has their product designed to fail just so you can go out and buy more. That's a myth from the 70's, and a sure fire way of having your lunch eaten by a competitor. The truth is that companies will sometimes dial back on quality in their product to produce one at a cheaper price....a completely different phenomenon.
I'm not so sure, to be honest. As a software engineer, I see a lot of abuses of this in the consumer electronics industry. Apple is the principle offender, most of the functionality they make you buy new hardware for is purely software and does not actually require the incrementally upgraded hardware that you're required to pay out the butt for. They revived the very business model you're claiming was a myth originating in the 70's and propelled themselves out of the niche content development market and into a trendy consumer electronics giant using it.
Hardware wise, I think you're right. But software wise, planned obsolescence is absolutely done on purpose by any company that finds itself in a position to do so without losing customers in the process. Why offer an iOS upgrade, when you can sell someone an entire new phone / multi-year contract?
LG's not in a position to do this, for sure. I have never in my life heard anyone talk about Goldstar / LG brand loyalty. It's traditionally been the cheap alternative to something else. But by the same token, they're not going to design their products with legendary reliability. Corners will be cut to reduce cost, and those corners mean that products don't last eons and are not user serviceable like they were 50 years ago; you do make a profit when someone has to buy an entire replacement product rather than swapping out vacuum tubes.