how come most full movies, today don't match the entertainment value of this old mere movie trailer?

I find movie industry, contrary to music biz, better than ever this decade.

Movies are as great as they always were if not better.
Technology makes it possible for independent directors to shoot quality movies.

Some of the very best movies ever were made in the last 10-15 years. Think about Gilliam, Burton, Lynch, Jonze plus all the commercial blockbusters which have great entertainment value.

On top of that it is probably the best decade for serial drama television, with amazing, innovative scripts written and quality, big budget, movie-like production.