Rambam quotes two pesukim by the mitzva of providing tzedaka to non-Jews:
הֲרֵי נֶאֱמַר (תהילים קמה, ט) “טוֹב יי לַכּל וְרַחֲמָיו עַל כָּל מַעֲשָׂיו”. וְנֶאֱמַר (משלי ג, יז) “דְּרָכֶיהָ דַרְכֵי נֹעַם וְכָל נְתִיבוֹתֶיהָ שָׁלוֹם
Pretty clear that there is a much deeper and fundamental aspect to “darkhei shalom” than just ‘keeping the non-Jew’s happy…more like emulating God and extending mercy to all his creations, as per the pesukim.
As for the Meiri, various poskim pasken like him or present a similar position such as Rav Yaakov Emden, Tzitz Eliezer, Rav Henkin, Rav Kook, Rav Ahron Soloveitchik and Rav Dovid Zvi Hoffman.
If you don’t respect a godol hador because they are a “Zionist”, you have bigger problems than whether to give tzedaka to non-Jews.