You either believe in pluralism or you don't. Unfortunately some parents do not want their children to learn progressive values. This is also true in the UK, unfortunately a lot of those parents happen to be Muslim - and so you have white liberals tiptoeing over the choice to be islamaphobic or homophobic. It's a mess.
Bigot means an inability to listen to the other side. It doesn't mean 'people who disagree with me'. What you've identifed in the education professional is someone not acting as a bigot. He's trying to find a middle ground, he's not throwing trans kids under the bus. The inability to accept that parents have a right to remove their kids from things they don't want them to learn - is an equal and opposite bigoted position to take. And here's why it's short sighted....
Kids hate being excluded. Trans kids hate being excluded and they often are. All kids have an aversion to being outside of the group. Their parents might not want them to listen to 'Call Me Max' - but the second they're removed from that class and told to go and do something else, all they're going to want to do is listen to that damn story. And kids are rubbish at keeping secrets, so other kids will tell them what was in the story. They'll find out anyway and they'll say things like 'My Dad says trans people are wrong' and other kids will say 'Why?' and they'll have no answer. Kids aren't a political tool, they're not here to be used as an expedient weather vane for progress, they're the next generation.
And so, compromise does look like progress, to anyone who understands how children think and how much of a win it was simply to get the book into the education setting. The last thing anyone needs at this crucial juncture is a bunch of activists from both sides galloping in with the tact and diplomacy of an amphetamine laden rhino. Chill. Progress doesn't have to be smooth, there will be bumps. Bumps are fine. Take the heat off because we're talking about the fragile world view of five year olds.
Oh, call me penguin.