How about trying to understand what people are telling you. I also don't see it as a RIGHT. The FACT is that Qantas says that I get certain benefits if I fly X amount with them. I've done the fly hence I am allow to access the benefits. Or are you saying I'm selfish because I expect to get access to benefits that I have paid to have?
I do understand what others are saying, I just don't agree. As I said I think many are just being totally selfish and childish about it. Just read some of the posts on here. Also you will find that those terms and conditions you quote can change. So yeah have a whinge but move on.
You're also missing a massive point, this is not about being a good customer in the past - it is about retaining good customers in the future, encouraging loyalty. This is about what is going to make people be loyal to qantas, what is going to make Qantas BETTER than other airlines - not the same as other airlines. (there is an answer to your "basic" question, which just happens to miss the point entirely)
I do see that point and it is very valid. But it does not answer my basic question of what business allows customers of their competitors to use their facilities, just because in the past they have been loyal.
Finally am I selfish, or am I looking after my own best interests. Looking after myself went I fly. I want to be comfortable when I fly, I want to use a lounge when I fly. It used to be that I got that from Qantas, now I don't. Qantas doesn't fly to Ceduna or the gold coast do they? If qantas doesn't value all the flying that I do with them and don't want to continue to get all that flying because sometimes I might need to go somewhere that qantas doesn't fly - then I would have to be stupid to not get lounge access elsewhere if I can get it. That is not selfish. You might feel smugly superior because you continue to let qantas walk all over you, but sorry that is not selfless it is just plan stupid.
That is all fair except clearly the business should be giving you the reward/benefit for using their services, not that of their competitors. And it has nothing to do with not valuing your past travel, after all that is what the frequent flyer program is all about. To me it seems fair for you to get that benefit when using THEIR services, not that of a competitor.
edit:
Actually thinking about it more, you basic question is based on a false premise. Qantas has said if you buy 1400SC of flights then we will give you platinum status with these benefits. While anytime access remains then using that access is using qantas' facilities as a customer of qantas - anytime access is granted on the basis of what you buy from qantas - not as a customer of another airline.
Again true, except they have now changed the terms and conditions to make that point moot, again their right to do under the same very same terms and conditions.
Bottom line is yes it is taking away a benefit that was once there, but that is life and business both of which are full of change.