The reason weather prediction has become seemingly worse is because part of that forecast was based on using historical data to anticipate future events. That data isn’t as great of a source now since things have changed, so they’ve had to extrapolate as best they can based on science of how weather systems work. Sometimes they get it close, something they totally miss.

As others have said, climate science is looking at a much bigger picture and trends with a different goal. I do disagree with title though - while the overall trend has been close to what was being warned about, the specifics have changed because we were limited then in what we knew and could measure, and there are things occurring that we couldn’t have guessed about that will make things worse. The trend is still in the general direction, just how much of a change and how it affects conditions that drive weather change as we learn more.

Basically, you can’t say that past models were perfect in their predictions and then have decades of “it’s worse than predicted”.