By the way, the Law required the Israelites to live in tabernacles made from native materials during this time period, and they needed to be kept in Jerusalem.
I know that most modern-day "Hebrew Roots Movement" people DON'T do this but they live in tents. Some stay in hotel rooms. Jews in Jerusalem live in shelters constructed on their balcony or something.
So, almost no one observes Tabernacles, in particular, in the biblically prescribed manner.
And, even if one allowed that they could observe these days in their area, in some years, it is freezing cold in that time period. I belonged to a cult that demanded their membership keep these days. One of the meeting places was Wisconsin Dells, Wisconsin. In many years, it was so cold that heaters were required in the meeting hall.
So, there's no way that the average person is going to live in a Sukkot in these climates.
The days were meant to be observed in Israel, and they coincided with the agricultural cycle in this land. They were not meant to be universalized across the entire earth.
Now, if someone wants to observe them in some sort of way, I don't care, but claiming that everyone must observe them is wrong...I can't imagine an Alaskan dwelling in a Sukkot made of plant life from Palestine in frigid temperatures.
That's why these groups have to modify their observances in a significant manner, and basically change God's law in order to claim they are observing them. Which is exactly what they claim non observers are doing
I finally figured that out years after I left the Judaizer cult.