Can't tell if shirt isn't cut right for me or if I'm just delusional

I have these modal cotton short sleeve shirts from Uniqlo: https://www.uniqlo.com/be/en/product/modal-cotton-blend-short-sleeve-shirt-open-collar-464938.html There's zero button on the collar so in the picture I have essentially every button buttoned. I'm more going crazy cause it feels like it shows a good amount of chest no? There's not even really a choice between 1 or 2 buttons unbuttoned, if I were to unbutton that top button I'd be showing everything. Does the shirt just fit bad or what? Then again, you can see in the Uniqlo styling pics, if bro was not wearing that undershirt it would probably fit me about the same. I just don't like undershirts at all, don't think it looks great with these types of shirts. Is something wrong or am I just completely delusional? Cause otherwise length / tightness fits great, perfect casual looking shirt I feel. TLDR: Is this shirt cutting too low or am I fucking delusional, i legit have every button buttoned but thats definitely the intent of the shirt so im clueless

Modal Cotton Blend Short Sleeve Shirt (Open Collar) | UNIQLO BE

Supple fabric with an elegant drape. Relaxed cut for easy layering.- Special wrinkle-resistant processing. - Cotton and rayon blend fabric with a smooth touch and moderate drape. - Relaxed cut with slightly dropped shoulders. - The loose fit means this shirt styles as an outer layer or on its own. - Handy chest pocket.- The images shown may incl...