My experience is (almost always) the opposite. I have found the quality of service has improved steadily (both in First and in business) over the years. However, there exceptions.

I recall one flight where the female F/A was rather lazy early on in the flight. The purser came to the First cabin and introduced himself to all of the passengers. When he came to me he told me that I was lucky to have one of the best F/As they had. I replied (politely) that she had actually been completely lazy and had not been doing her job properly. She must have been given a telling off, because from then on she was great!

If I ever have a negative flight experience (or for that matter a particularly excellent experience) I always write to EL AL customer services. No business can ever improve without customer feedback, so you have a vested interest in writing to give such feedback if you want things to improve. I know for a fact of a number of things which have been changed as a direct result of some of my feedback.