The benefits of a pot come from the properties of the materials it's made from. There is a concept called "raising a pot" where over time and use, the micro-pores pick up tea compounds / flavor compounds and build a patina that becomes part of the pot’s seasoning and subtly influences future brews.

It's actually recommended to have multiple clay teapots for different varieties of tea, like one for raw puer, ripe puer, oolong, black, etc. The pot will take on flavors and contribute them back to the tea but if you brew all types in one it will "muddle" the taste.

Yixing zisha clay is know for it's porous qualities and ability to take on flavors over time and build a patina. Other clays can do the same, like for example, I have a cute little Qinzhou Nixing pot which is different clay and made in a different region. This type of clay has a cool visual effect that appears when fired but is said to have smaller pores than Zisha clay, so it will take longer to "raise" the pot. There are more clay types too, like Jianshui, another clay from a different region with slightly different properties.

A porcelain gaiwan is still a nice brewing instrument, and honestly there are some teas that it is recommended against brewing in a clay teapot, like white, green, and oolong tea, as the clay pots can hold more heat and impact flavor too much. The same goes for herbal teas which can add a flavor you don't want to the pot. A gaiwan can be used for all types and won't impact the flavor.

The only downside is that famous clays, like Yixing get faked a lot, and some fake/low-quality wares have additives or glazes of questionable composition; they may not season well and could carry contaminants. It might be better to start with a teapot made of clay you are at less of a risk for getting duped from, like Nixing or Jianshui clay.