In my opinion no it is not necessary. High mileage oil is "suppose" to help engines not burn as much oil due to the additives they put in their for the seals etc. I have had multiple cars with well over 100K and I always use conventional motor oil but of course it is up to you
I wouldn't bother unless you're burning/leaking an annoying amount of oil. If the oil is leaking by valve or case seals it will probably help.
The additives work by soaking into and expanding the seals. But once you've done that you need to stick with high-mileage oil or the seals will shrink again and probably leak even more.
I started using it at bout 160K, noticeable improvement in oil retention. I actually switched more because my other car (land rover) had some case seal leaks... since they both use the same oil I just wanted to keep it simple.
What it won't help with is bad rings haha, but that's not a problem any of us are likely to have unless you're really bausing it.