The Gemara teaches us that in the generation when Moshiach comes, the Galilee will be destroyed (Sanhedrin 97a):
During the generation that the son of David comes, the hall of the assembly of the Sages will be designated for prostitution, and the Galilee will be destroyed, and the Gavlan, i.e., Bashan, will be desolate, and the residents of the border who flee the neighboring gentiles will circulate from city to city and will receive no sympathy.
Similary, the Zohar (2:7b:5) explains that Moshiach will reveal Himself first in the region of Galilee:
בְּהַהוּא זִמְנָא, יִתְּעַר מַלְכָּא מְשִׁיחָא, לְנַפְקָא מִגּוֹ גִּנְתָּא דְּעֵדֶן, מֵהַהוּא אֲתָר (בלק ק''ד ע''ב) דְּאִתְקְרֵי קַ''ן צִפּוֹ''ר, וְיִתְּעָר בְּאַרְעָא (ויקרא רי''ב ב') דְּגָלִיל, וְהַהוּא יוֹמָא דְּיִפּוּק לְתַמָּן, יִתְרָגַּז כָּל עָלְמָא, וְכָל בְּנֵי עָלְמָא מִתְחַבְּאִין גּוֹ מְעַרְתֵי וְטִנָּרֵי, דְּלָא יַחְשְׁבוּן לְאִשְׁתְּזָבָא. וְעַל הַהוּא זִמְנָא כְּתִּיב, (ישעיהו ב׳:י״ט) וּבָאוּ בִּמְעָרוֹת צוּרִים וּבִמְחִלּוֹת עָפָר מִפְּנֵי פַּחַד ה' וּמֵהֲדַר גְּאוֹנוֹ בְּקוּמוֹ לַעֲרוֹץ הָאָרֶץ.
The question is as follows: why does the Gemara teaches us that the Galilee will be destroyed in the generation when Moshiach comes? I've heard from my Rabbi that the fact Moshiach will come first to Galilee symbolizes healing, since this was one of the first regions that were exiled (2 Melachim 15:29). But why does the region first needs to be destroyed?
Does "will be destroyed" literally means destroyed, or does it symbolize spiritual destruction like as in "The wisdom of the Chachamim - will become rejected"?
Also, based on which pasuk does ר' יהודה say that this will happen?
As always, (contemporary) commentaries, insights etc.. are very welcome.