Are 4 seeds typically as good as 1 seeds?
On the S-Curve you're looking at teams 13-16. Typically just outside the range of your most likely contenders.
Obviously 4 seeds have a much tougher path. I think 1 seeds are winning the title at a higher rate has more to do with the fact that you're dealing with a dominant team, whereas 4 seeds are good teams, which usually have a ceiling of the Final Four.
Here's one of the more interesting tournament stats.
2nd Round Wins
8 seeds- 13
9 seeds- 7
10 seed- 23
11 seed- 24
10-11 seeds have more than double the 2nd Round wins as 8-9 seeds. The 8/9 seeds are getting crushed in the 2nd Round by the 1s. Collectively, they're winning less than 14% of the time (20-124). And it makes sense because they're playing a top 4 team.
10/11 seeds, on the other hand, are a combined 47-64 (42.3%) in the Round of 32. The 10-11 seeds are presumably worse than the 8-9 seeds. But, your odds of advancing to the Sweet 16 are much, much higher as a 10 or 11 seed if you face a 2/3 seed in the 2nd Round.
Edit: I was looking at this
page for the tournament records, which I believe goes back to when the field expanded to 64 teams in 1985. I added on the 2021 numbers myself. Looks like your page goes back to 1979, when seeds were first introduced. So, there are some slight discrepancies in the numbers.