Obviously yes, as the boards of Japan are 99.99% Japanese.
The most popular boards are actually textboards and not imageboards, so something like memes do not exist in the Japanese internet as we know them and the word Miimu wasn't even known there until maybe two or three years ago, the "cool kids" on Twitter and Instagram would start to post Pepe and larp as a foreign meme pro.
Also, these textboards have a massive userbase and therefore a huge impact on society.
Tons of artificial words are created there and many of them will find their way into every day Japanese a few years later. The amount of internet slang in Japanese is incomparable big compared to the English one.
I'll give an example.
Pic related is the explanation how the Chinese character for grass, 草 (kusa), is now widely used for "lol", even by chads and stacies. Some people even say it irl but that's cringe.
笑う means to laugh, and its pronunciation is "warau".
In the early days of the internet, only 笑 (wara) was used as a smiling emoji replacement.
However this was annoying to type, so people just wrote a "w" at the end of a sentence, and the funnier something was, the more W's they would add at the end, pic 2 is comments on a random video.
Now, some people said "wwwwwwww" looks like a grassfield, so the chinese character for grass, plant is now the new "lol".
There are even expressions like 大草原不可避 which roughly translates to "The steppes are inevitable" and basically means ROFL, or LMFAO.
Words like this on fucked up ways are created every month, they come and go, some stay, others don't.
