The subject of Rav Avraham Abulafia was known to people even before his books were published in Jerusalem and are being sold in Mea Shearim book stores. Mainly the reason is that Professor Moshe  Idel made his PhD thesis about Rav Abulfia and later published  a whole series of books on him and on ecstatic kabala. The attitude of Rav Abulafia towards Yeshua was contained in his PhD thesis.

But some people knew anyway. Rav Avigdor Miller knew. I asked him if he was aware of Rav Abulfia and he said, "Yes". One reason he is not known is that kabalah took a different track after the Middle Ages. Now it is almost synonymous with Zohar. But to me that seems to be a mistake. Even though the Ari himself merited to great levels of Divine Spirit, it seems to me that whatever was based on the Zohar itself does not have much merit.
 Mystics in general were not lacking. There were plenty of Jewish Mystics that had revelations. But when they base themselves on the Zohar, it seems to me they get off track.

[The main problem I see with the Zohar is עם כל דא a translate of עם כל זה. And עם כל זה was made as a phrase to substitute for אף על גב or אף אל פי--"even though". But this phrase על כל זה was invented by the Ibn Tibon family. So what is it doing in the Zohr which was supposedly written a thousand years before the phrase was invented?