There are two key conflicts. First whether Pride should remain as celebrating and “normalising” gay relationships by showing gay and lesbian couples as being “like everyone else”, or whether it should be about celebrating the broader range of sexual interests as it is now starting to including the fetishes of straight and gay people.
Sexual orientation is a protected characteristic under the Equality Act for very good reasons.
Getting your kink on in the high street is not.
If you want to campaign for that then fill your boots but be honest about it and expect strong resistance.
Being lesbian, bisexual or gay should be normalised because it is normal and it harms nobody. LGB people are just like everone else. Making everybody else join in with your exhibitionist BDSM fetish whether they like it or not, whether they're aware of what you're up to or not, whether they're adults or children, is not normal. It's grim as fuck, abusive and dangerous.
The people advocating for kink at Pride are saying Pride shouldn't be advertised as suitable for children. Why aren't they taking this up with Mermaids?
www.stonewall.org.uk/about-us/news/solidarity-and-pride