Any advice of beating counter spell bullshit with a mono red Purphoros deck?
Given that it's brawl, that takes away your best two options (splashing blue or black). If your deck relies on casting one expensive thing, you need to accept that it's inherently vulnerable to counterspells.
Here's what you can do: the already mentioned crawling barrens, mazemind tome to outdraw them (if they don't have a draw engine of their own, the counters will stop at some point) and cards with cheap escape cost:
beniz of ash eats three cards, Underworld Rage-Hound eats three, satyr's cunning eats two, force them to counter this over and over and wear them out.
The main reason I haven't built a serious historic deck yet is I know i'm gonna have to deal with the land destruct fags. I might get around to it eventually though.
Last time I've ever seen a dedicated LD deck was two years ago when Dominaria was a thing. I don't think people even remember that Haphazard Bombardment and Fall of the Thran was a thing, nevermind having the wildcards to craft such niche rares.
The format is way too fast for this shit anyway. Goblins don't care about you blowing up lands on turn 4 when they've already have skirk prospector and krenko engine out and Auras is already on it's way to deal twenty.
So, I figure, as the emote goes: you worry too much.
It would be interesting to try out the Ghost Quarter with Crucible combo together with Cleansing Wildfire (perhaps in some kind of a landfall shell) to punish greedy decks packing nothing but nonbasics,
but that's unreliable, especially in Bo1 when monocolored aggro is the default deck you'll be seeing.