I have never mulched our 25 yr. old bluegrass-rye lawn. What are the advantages & disadvantages?

I have never mulched our 25 yr. old bluegrass-rye lawn. Have always used the catcher and dumped the clippings in the proper pickup bin. What are the advantages & disadvantages of mulching rather than dumping / discarding?

Thx

Mulching spreads weeds. Chokes the turf of water and nutrients. Long story is mulching came about as another way to sell a mower. Is it better than bagging? No. Bagging lifts the grass up for a better cut slash look. And those mulched clippings don't break down either. As in totally removed from the turf. Why is mulching so popular? Because in "fat lazy America", lazy items will outsell items that take a little effort.