The US was a lot of things. It still is on some fronts, but others have seen decline.

Your experience was certainly true. It is why so many are trying to come here. But things have changed and the experience is not what it used to be. If you think it was difficult before, think about how it has to be now for people to choose to go back instead of persevering. The trend is clear. Things changed. The US can either fix it and remain competitive by hoarding talents. Or it will continue to deteriorate.

There are always warning signs. Immigration laws has been called antiquated and desperately in need of reform for a long time. Your sentiment of "it was good in my time" is how hegemons like Britain fell.