Good question
Speaking as an uber-introvert. I hate asking for things. I hate making people say "no" when I can leave things open and have them offer (or not) I hate putting people out
I'd be hesitant to tap the x-card and inconvenience anyone, even if I was uncomfortable. Even if I suspected everyone would stop for me. Because I'd rather be uncomfortable than force anyone else to stop having fun
For me, having lines and veils established in advance would work better than an X-card. Because I'm going to feel confrontational tapping the card. I'd prefer the DM not "going there" in advance
Your bringing up two topics here that blend together a bit but deserve their own discussion The
tendency towards agreeableness shoving your own needs aside & the x-card pressure. That agreeableness is a perfect example of why your GM or your player needs to engage in discussion with you or any other player/gm to sketch out what you are asking for them to (not) do before they can give informed consent to (not) doing it. That discussion also allows you the chance to demonstrate that you acknowledge& understand the risks that you are agreeing to.
In medicine & other communities with a strong culture of consent that process is known as
informed consent. Informed consent can't happen if the person consenting is not able to demonstrate that they understand the risks & responsibilities well enough for other involved parties to give their own consent to your wants & needs through discussion The tools need to accept that humans aren't always logical & design themselves towards proactively avoiding this kind of snag .
wrt your "I'm going to feel confrontational tapping the card", You might justifiably be hesitant to stand up, reach over the table, & feel the way you are certain everyone's eyes are drilling into you* while you touch the x card instead of just fixing that one mini not quite centered in the square beside it . You are going to have a much easier time jumping in & saying
"I want to look out the window to see if I see anyone hears this carnage". You could fix that mini & it would be really easy to point all those eyes at the mini instead of you by fixing it so you can sit back down.
When things like status checks & safewords for communicating enjoyment & comfort levels are normalized it's a much lower bar than feeling all of those eyes for you to just say something like
"I want to look out the window to see if I see anyone hears this yellow carnage" and let everyone know that you are asking them to either not dial this up a notch or change things up perhaps like this by mentioning people maybe hearing it.
*it doesn't matter what everyone else is doing for someone to feel confrontational taking the first step & it's a pretty well documented behavioral thing.