Is it a common belief that the Moshiach is coming very soon?

I had always heard about the belief that the “end times” will start after the year 6000, and that it can even happen earlier if every Jew follows the Torah prior to the arrival of the Moshiach, but recently I also learned about a belief that the Moshiach will arrive 200 years prior to the year 6000 (in the year 5800), and that the Moshiach will rule in Israel for 200 years prior to the end times. Well the current Hebrew year is 5783, and 5784 begins next month, so the implication here is that the Moshiach will arrive within the next 17 years.

When I heard this recently for the first time it honestly shocked me. Is this really a widespread belief for religious Jews? The person who told me about this informed me that it’s written in multiple places in Jewish texts, and that they see it as reality that the Moshiach is guaranteed to come in this lifetime. The belief also entails that if every Jew is not following the Torah before the Moshiach arrives, then the Moshiach will bring about the end times through violent means instead of through peaceful means. So is it really common Jewish belief that 17 years from now the entire world will enter into a state of war?