Author talking points and author background might give a reviewer or journalist something to write about.
1st-time fiction authors are – publicity wise – a dime-a-dozen. If there is a way to talk about the book and it's author, some "angle" that suggests the main character is unique and authentic because it comes from a unique and authentic experience, that's a way to market both the novel and the author together. There is no such thing as bad publicity.
However, no one wants to be a "token", or to be presumed to be writing the narrow, insultingly stereotyped "I'm a people too" type of minority characters penned by non-minorites. If you don't feel drawn to fight the tide of reader expectations and existing societal limitations, sure, skip that battle. Write the story you want to write.
You might end up writing a different story about a completely different protagonist that gets published before this one, so you could always make the talking point that you are a writer writer, not a minority writer.
You can also just avoid talking about yourself completely. (Reviewers will have more to say after your 2nd novel because there will be something to compare and talk about.) We should all be so lucky as to want to be left alone by publicity hounds, like Garbo.
Have your cake and eat it
I'm pausing at the part where you say:
I hence changed the novel’s genre (from romance to thriller)
You've punched up the novel and made it more exciting (?), or am I hearing the expectation is that minority protagonists are relegated to romance stories, and thrillers are out-of-reach or too far fetched? If that's the case I'd try to challenge that expectation because it's limiting your options as an author – even if it's true and "minority thrillers" are not a marketable product.
There are historical settings where every character is an immigrant or indigenous minority: San Francisco gold rush, New York's Five Points, London's Limehouse. You can create a situation where the majority population, who presumably control the local power structures, become the outsiders and your minority MC has the unique perspective.
I don't want to read too much into your story, but a thriller can explore issues of minority vulnerability: fear of police, mistaken identity, invisibility, mafia. Those same vulnerabilities would be all kinds of trigger-warning in a romance (!) but in a thriller with healthy suspension of disbelief, I think there are more excuses for a reluctant detective, or some family drama call to action, or protagonist is an outsider in both worlds.
Maybe that's the kind of minority cliché you want to avoid, but "generic" protagonists have these things. If it works as a pretext to action, you can still have the MC be self-aware and comment on it. You can also play against those kinds of tropes. Do both. There's a something there with built-in dimensionality. Exploit what you like and pretend the rest doesn't exist.
Put it in the story
You can even add some aspect of your qualms into the story. I generally feel where there's a story issue I debate – should I, shouldn't I – the debate itself is probably more interesting than my idea. How can I storify the very debate I am going back and forth about? Maybe there are 2 characters, one for and one against. Maybe the character over the course of the novel experiences both sides of the issue. Maybe (especially if it feels too personal) I can choose a "safe" avatar to explore the issue that doesn't feel like it points back to me.
I like characters with a unique perspective, and I like underdogs who have to work around other people's limits and expectations. I like characters who are more than their stereotypes, and yet who are self-aware and exist within my universe of experience (indigenous minority). That character doesn't need to look like me or have my specific experience for me to relate to them and trigger my empathy.
Protagonists work better when they are underdogs and are forced to think outside the box and problem solve. Chosen One protagonists that discover they have a fantasy birthright by virtue of their genetics do not appeal to me at all.