If the percentage of LGBTQ people will continue to double every 10 years and the current percentage is 7.1 then the equation for when everyone is gay is this (with x being the number of decades)
7.1 * 2^x = 100
x = log2(100/7.1)
x = 3.81604 or about 38 years.
Since the tweet was made in 2022, the current trend would suggest that everyone will be gay in 2022+38 = 2060, not 2047.