As severe congestion continues on the M50, the prospect of multipoint tolling is in the news again
https://www.independent.ie/irish-news/m50-drivers-facing-more-toll-points-in-bid-to-tackle-traffic-congestion-36592474.html
IMO this would be viable if Dublin had a functioning mass transit system. It doesn't. There is no alternative to the M50 for most people on it. They aren't spending so much time commuting because its enjoyable or beneficial to them.
Cart before the horse once again.