This is a really big question.
And it is several questions, that need to be answered separately.

1) Should "old" people be respected, because they are older? In a world that is turning its back on the old ways, the old people do not have much in the way of guidance towards the new.

As in, we, as a planet, are moving into peace. World peace is happening, however all of the old warmongering, and all of the hippy-dippy anti-war people all say stupid things that prevent peace from existing.

So, if you listen to the old people who say, there is an enemy behind every rock, or the old people that say "never judge anyone" than you will be kept from this path of peace.

2) "Old people are wiser". This may have been true, before TV, brainwashing and propaganda made most of the people merely broken records of propaganda gone by.

They have never learned any wisdom. They are only a collection of sound bites. And it doesn't matter if you are 20 or 80, these people have almost nothing to give a future society. They are not wise, in fact, most haven't even thought.

3) There is a lot of information that can be learned from someone who has been there / done that. It looks like we are repeating the cycle of the great depression. With tent cities and everything. And it would be good if we listened to those who did this before.

We are repeating the same cycle that brought hitler to power. There have been many aged Germans in america who have said, "they said the same thing" (back in 1940)

However, with our bias against the non-tech savy old fuddy-duddies. We do not listen. Like, really, what do they know? Besides, that generation left us to fend for ourselves, home alone, as they went to work and socials.

So, what i look for is wisdom. Whether the person is 5, 25 or 75. I honor wisdom.