Psalm 49 encourages us to put our focus on God. We all have the same fate: we perish. Even though wicked, sinful people “succeed,” their success is in vain because their end is to “go to the generation of his fathers, who will never see light.” When I read the last verse:
20 Man in his pomp yet without understanding is like the beasts that perish.
… it seems to me to imply that man with understanding is not like the beasts that perish. To have “no understanding,” in the context of Psalm 49, seems kind of like to be near-sighted – either an incorrect long term outlook, or none at all. Those with a reverence for God and an understanding of what God desires will rule over those who follow a path of foolish confidence – consider Psalm 49:12-14
12 Man in his pomp will not remain;
he is like the beasts that perish.
13 This is the path of those who have foolish confidence;
yet after them people approve of their boasts. Selah
14 Like sheep they are appointed for Sheol;
death shall be their shepherd,
and the upright shall rule over them in the morning.
Their form shall be consumed in Sheol, with no place to dwell