All roads lead to Rome right...??
Dedicated climbing sessions or dedicated workout sessions - both have to have some benefits.
Now with things like Zwift/Rouvy... - those of us with winter weather can be light years ahead coming out of the winter when compared to the dumb trainer days of old.
Do the workouts to train the body for the specific events, do efforts mimicking doing the specific events... that's what I'm doing along with intervals.
I did the 4 Horsemen route on Zwift yesterday - 7k' of climbing in the first 30+/- miles. For me it was a brutal workout - took me to my limits and beyond... I have to think there is positive benefit to workouts like this. That it will absolutely help in real life.
I start my interval sessions in a couple of weeks - I can't see a downside in throwing in a weekend "climbing" session every so often.