Over time Crosby, Sintra, Elvis all 3 set the tone for music in todays singing.
The past makes today possible.
What I have noticed is todays singers sing a bit offkey and get away with it.
You didn't hear that musch years ago untill folk music came along, and most todays music is a folk rock sound. There are a few great guitarist still wh sing, but not many.

lolwut

Sinatra is from an era of people who don't really sing, they just do what I call, talk sing. Not rapping but not really singing either. I don't know...

I love Frank Sinatra. Buble made him popular again, but of course the original is always far far better. I like how he has an orchestra everytime he sings live.

https://www.youtube.com/watch?v=heGRvVBaB68