He did not mention a time period.
You could say gay rights were achieved in 1980 when sex between men was decriminalised in Scotland - frankly, I'm sure plenty of LGB Alliance supporters would have left it there.
Or you could say it was 2014 when marriage equality was achieved.
Either way, whether there have been big increases in the number of gay people in every generation.
"Research by Ipsos Mori found that 66 per cent of young people, aged between 16 and 22, are "exclusively heterosexual" - the lowest figure of any generation.
Among millennials, 71 per cent say they are exclusively heterosexual, as do 85 per cent of those in "Gen X", and 88 per cent of baby boomers."
www.telegraph.co.uk/news/2018/07/05/two-thirds-generation-z-identify-exclusively-heterosexual/
Whatever way you spin this, the baby boomers grew up in a time when there were less gay rights (i.e. it was banned).
Now we have rights (I think we can all agree) and there are so many more people in Gen Z who are LGBT.
He is either badly informed or lied to the Scottish Parliament. He should be banned from giving evidence to any legislature ever again. That is the only way to tackle misinformation.