No, a tight top, euro top, and pillow top mattress will not feel the same. Each of these types of mattresses has a different construction that affects the feel and support provided to the sleeper. (Almost completely wrong, except on the outside couple of inches of your mattress where a tigh top mattress might waterfall) (waterfalling is a term that describes the gentle curve of the fabric on a mattress that runs from the top panel to the side panel)
A tight top mattress is the most basic type of mattress, with a flat surface and no extra padding on top. It provides a firmer feel and less cushioning. (100% not true as each type of mattress can contain the same comfort layers and be quilted in the same pattern and thus feel the same)
A euro top mattress has an additional layer of padding sewn on top of the mattress, which provides a softer feel and extra cushioning. The euro top is sewn flush with the mattress edges, so it can be difficult to distinguish from a tight top. (euro tops and pillow top mattresses are almost completely cosmetic differences form tigh top mattresses)
A pillow top mattress has a layer of padding that is sewn on top of the mattress, but it is thicker than a euro top and often has a distinct border. This extra layer of cushioning provides a very soft feel and a plush sleeping surface. (Simply not true, see above)
So while all three types of mattresses may look similar, their construction and padding differ, leading to different levels of firmness, cushioning, and support. (That they do not look the same is pretty much the only reason you might want to pick a mattress model that is not a tight top. You should always pick the most comfortable mattress model, that fits your budget, that you try in a showroom)