Oh, I agree that mobile first would have been optimal.
I prefer classes to p+p (or #footer p + p etc), it’s easier for me but I know it’s not the only option.
If I have 5 paragraphs it could get difficult but each to their own.
I’m not fussed about anyone looking at my HTML. It’s only going to be another developer doing so and at least if I have a class attached they know instantly where to look….but as I said, it’s a personal choice.