I dunno, I always did OK with my 1-handed backhand, won some club championships with it. Was invited to compete as an amateur nationally, but I knew my small stature was against me, especially as the "power serve" began to dominate men's tennis. I had speed, agility and accuracy, but never great power. The game was changing from when I began in 1963.
And then my right wrist tendon went bad for a while, knocked me out for several years. I was already in the Army before it fully recovered.
The first player I knew to use the 2-handed backhand routinely was Jimmy Connors. He was known for it. I'd followed him when he was still an amateur, a little younger than me, turning pro I think around 1972. I never adopted the 2-handed.