Philosophers on Twitter getting push back about The Letter: here are some candidate actions, and some evaluations (by me) of those actions (thread):

i) Say nothing, refuse to engage
Evaluation: You have made a public stand: this makes you publicly accountable.

ii) Try to laugh it off.
Evaluation: This is a serious matter (you accept). Please don't ridicule those who disagree with you. You want to be taken seriously: take your interlocutors seriously.

iii) Straw-man your critics.
Some people will tweet that you are an effing misogynist. But other people will make polite and serious objections to the text of your letter: address the strongest objections to your claims, not the weakest.

iv) Fail to answer the questions posed.
I would like an answer to my question: what is the difference between a view being trans-exclusive and a view being transphobic?

v) Say 'I'm tired, I've got a lot on my plate'.
We are all tired, we all have a lot on our plate. But you have made public statements, to which you have lent your reputation, and you have an obligation to respond to polite critics.
(& join the union, ofc.)

vi) Make vague claims without evidential support or good reasons. Fail to specify concepts clearly. (Here, concepts like 'trans-exclusive' and 'transphobic', both of which appear in The Letter)
Please don't do this. It's not good. People are watching.

If items (i)-(vi) look familiar, from your first year teaching (if you still do any) from 'how to write a philosophy essay', then that's not completely unintended, and not completely coincidental.

And in response to the inevitable comic strip, when it comes to sea creatures, I much prefer Stingrays to Sealions. (see bio if necessary, but I bet you'll get the reference)