The oppression in previous generations definitely is a big factor.

The second big thing is that the majority of LGBTQ+ people is bisexual. And there were a lot of bisexual people who would, in previous social climate, identify as heterosexual due to living in a heterosexual relationship.

When you dig into the data of several other surveys, it becomes even more apparent that the seemingly rising number of LGBT+ is due to the removal of stigma: Earlier surveys had shown that the group that saw the biggest growth among all are bisexual/pansexual people while the other groups saw much less growth.

From an article in Psychology Today from 2022:

In the Gallup survey, most of those identifying as LGBT+ said they were bisexual: [...] 57 percent of those declaring themselves something other than cisgender heterosexual. [...]
Again, bisexuality was age-related. Those most likely to declare themselves bisexual were the youngest adults, with each older age group less and less likely to claim bisexuality.

An article in the Washington Post from 2021 makes the apparent "rise" of bisexuality/pansexuality even more obvious:

Research from the Williams Institute at the UCLA School of Law has similarly found that a key driver of the growth in the LGBT community has been a surge in bisexual women and girls. Bisexual women make up the largest group of LGBT adults — about 35 percent, according to a Williams Institute analysis of data from three population-based surveys. More than one in 10 U.S. high school youth identifies as lesbian, gay or bisexual. And among them, 75 percent are female and 77 percent identify as bisexual. [...]
Kerith Conron, research director at the Williams Institute, said more research is needed to understand this pattern. But, she said, “my theory would be it’s more acceptable for girls to identify as bisexual. The policing of young people is particularly pronounced for boys, to be masculine,” Conron said. “And for girls, to be bisexual isn’t necessarily perceived as a significant deviation from femininity.”

So people are much more open to talk about their sexual desires for people of the same sex once the stigma is removed, but - unfortunately for young men - that is less often the case for them, so they won't admit these feelings.

PS: Add that to the fact that women are much more likely to hold progressive politics than men.

I think the pandemic had a big impact as well. Social distancing meant that people were isolated from the forces that usually made them perform cisheteronormativity, and a lot of people realized "oh hey I'm queer actually".

I know quite a few "COVID queers", including myself.

Y-axis could definitely use some labels...

My bad... Percentage of total population!

Gen Z likely has a much more loose definition of sexuality and gender identity than the older generations have. The more loose the definition, the more people that can identify as part of the group.

Understanding gender and sexuality as fluid and as part of a spectrum is a difficult thing to learn when you've been taught the exact opposite your whole life. And Gen Z isn't old enough to be stuck in those definitions. Love it or hate it (and I do hate social media for many reasons), social media has been the catalyst for so much LGBT+ acceptance.

What's important: There is the letter B in LGBT. Half of the the LGBTs identify as bisexual. A lot more people now fell free to say that they are bi. More than before.

This is a news article about the latest survey: https://www.nbcnews.com/nbc-out/out-news/nearly-30-gen-z-adults-identify-lgbtq-national-survey-finds-rcna135510

One of the recent advantages with the newer generations cane with the internet which provided a place to create common nomenclature and symbols.

Take a kid who notices their own likes and sense of self doesn't make sense to their peers and vice versa. In my generation we just felt like an outlier, a deviant from the norm. With the internet LGBT+ community they can find these desires and behavior patterns are not unique, are not unhealthy or harmful, and there are others with like experiences.

There's also the matter that these groups are commonly marginalized much the way women and nonwhites are. Our community is united by the need to be regarded as equals by the state and by our neighbors, even when we are out (id est, who we are is known by our peers).

The conservative ones died while the LGBT and other progressives lived.

Can't fathom why

Down because of people.. you know.. dying

Up because of people coming out really late in life

Would be my guess

Maybe because of the GOP getting more aggressive in their anti-LBGTQ rhetoric and the rise of Trump?

The last 2 "blocks" are from 2 different survey institutes. This has probably caused the "jump".

The numbers were slightly, but continuously decreasing in Gallup surveys, but a lot higher in the 2023 survey of a different institute.