I've skied Vail just about every year since 89 and you might be surprised that I have not seen lift lines get significantly longer. Lifts 2,4,7,11 get 10-30 minute lines most days. Powder days have a totally different traffic flow but it's not uncommon for lift 5 to have 45 minute lines at peak times (easy to avoid). Base lifts also can get long lines in the mornings. All of these lines have grown fairly little for the last 30 years. I personally have not stood in a line longer than 10 minutes in years at Vail but I do avoid certain lifts at certain times. I also ski peak times such as new years and spring break nearly every year.
That said there were some extreme lines recently. The lines that made headlines were actually Feb 2020. (pre Covid) Some pretty rare factors collided:
- 38" fell in 48 hours. I don't have the stats but that could be the biggest powder day at Vail in years and definitely in the top 1%
- Due to avalanche work, more than half the acreage was closed.
- The most popular lifts of those open were dead end lifts (lift only way out)
- It was a Saturday
My main point is that these crazy-long lines are very rare. I actually love the smaller ski areas and mostly ski Vail so much due to family preference. Many of these smaller areas not only have no lines but have much lower density on the runs which is a big plus, especially when skiing with kids.
Despite my point about Vail lines, I do see more concentration of skiers at a few bigger ski areas. For a variety of reasons, most people value large ski areas. Some of those areas recently became large. For example, Big Sky has more than doubled in size in the last 25 years. In fact, just about every major ski area today had at least one major expansion in the last 25 years. Breck added peaks 6 & 7, Beaver Creek added grouse, arrowhead & bachelor, Snowbird combined with alta and added mineral basin, Snowbasin added strawberry and John Paul, PCMR more than doubled. In general, the ski areas that expanded were already popular and became even more so with expansion.
The remaining small areas have a more narrow appeal and stiffer competition but when they align with you, they're great. You also have some large ski areas that are remote that have great appeal if you overcome travel challenges. Both of those challanges are exaserbated by the fact that ski destination often need to meet the needs of a group/family with hetrogenious needs which are more likely to be met by big ski areas. For example, "mom" needs a base village, one guy needs expert runs, another needs cruisers, one guy needs a direct flight home, etc. Such criteria quickly excludes a lot of smaller/remote areas.