I'm not so sure he's stating he's a fan of Zenlenskyy (actual spelling of his name). He says it was great to be part of an historic speech--he doesn't comment on the speech itself, and perhaps he knows more about the event than we do. He also states that Zelenskyy makes it clear that Americans and Ukrainians are partners for democracy...we HAVE given them tens of billions of dollars. Also, we are not a democracy; Grassley would know this as a Constitution-defending Republican. The way he said Zelenskyy made it clear seems to indicate that Zelenskyy holds some authority in that setting.

I'm going to give Grassley's comment some time before I pass too much judgment on it.

EDIT TO ADD: I assumed Grassley voted against it. Husband just told me otherwise. Dammit, Grassley.