Many of the subgroups in that alphabet soup really don’t like the others (or at least their movement). It used to be GLBT before it became LGBT. Yeah, gays and lesbians are not fans of each other. The TQ* groups despises the bisexuals because the latter implies two sexes.
The word “bisexual” does imply two sexes, but the tendency of the movement is more towards “pansexuality,” that is, attracted to men, women, non-binaries, and whatever else there is. The difference between bisexuality and pansexuality isn’t that great. Deciding one is attracted to both men and women is more a denial of gender differences than an assertion of them.
Transsexuality is a product of technology, propaganda (or social media word of mouth), and politics. Before transsexuality became a fashion and a rival to LG, it more or less fit in with them. Men who identified as women hung out with gay men, and women who identified as men hung out with lesbians. The divide came when trans women wanted to hang out as women with women, and teen girls decided that they were boys, and not lesbians.