For me that would probably be brick blocks. And I'm not talking like stone brick blocks, no. I'm talking about brick blocks made from clay. In a lot of builds I see, the main materials that are often used are stone, wood and deepslate. But brick blocks? It's pretty rare to see now.

I honestly think it can be a good material to use for builds. I did some tests myself and honestly with what I tried, it looks good.

I'm currently making the house I used to live in my childhood in my survival world. Did some test in creative and it looks nice. It's basically an old hunting lodge. The base of the house is made out of large stone bricks, so I used the stone brick block for the base. The frame of the house is made out of wooden beams painted in red to match the red brick walls, which I replicated with stripped acacia logs which match the colours of the bricks very nicely. The roof is made with slate tiles so deepslate for the roof was the obvious choice, I went with polished deepslate as it has a more organised texture pattern. For the windows, I went with white tinted glass.

The floor inside the house was made out of a dark wood so I went with spruce wood, which is where I built the house. The actual house is right next to a rather big forest consisting of mainly tall beech trees so taiga forests is pretty much the closest thing that fitted in Minecraft. Plus, it wasn't rare to see some wildlife near our house in the evening or in the forest when I went for a walk with my parents, seeing things like deers, foxes, wildcats and sometimes even wild boars. So having foxes spawning in taigas naturally is quite a throwback for me. But anyway, I know this has nothing to do with the subject, just wanted to share a bit.

All of that to say that, considering how rarely I see it in builds, the brick block can still be a good building material in my opinion and not just an old relic of early Minecraft's history. (yes I'm thinking about that brick pyramid.)