Q:

Why did my Chinese teacher describe Donald Trump as 口吐莲花?

In my regular Chinese class yesterday, I was discussing Donald Trump with my teacher, and she described him as 口吐莲花 (kǒutǔliánhuā).  As always I didn't fully understand the particulars of the conversation, but I believe she was referring to his eye-catching, provocative speech and behavior (and contrasting it with Biden's lack of theatrics).  I'm interested in what about Donald Trump in particular makes him 口吐莲花.
Question: Why did my Chinese teacher describe Donald Trump as 口吐莲花?
It's hard to look up this term, e.g., YouDao gives "vomit a lotus" and Google Translate gives "spit lotus" which don't capture the non-literal aspects of this term.

A:

「莲花出淤泥而不染」，象征纯洁 (lotus flower came from mud but not stained by it. Symbolizing purity.)

Your teacher described him as 口吐莲花 in an ironic way,  mocking his foul mouth

Idiom 舌灿莲花: 譬喻说话的文采和美妙 ("the tongue sparks lotus flower" refers to having the literary talent to speak beautifully.)

Again, ironically, your teacher was mocking his lack of literary talent and his incoherent speeches

A:

口吐莲花 ( and 口吐芬芳） is a modern word online, e.g. in Dou Yin (TikTok Chinese version)
Mostly it's to show someone is saying dirty or ridiculous words.
Its original meaning is to say something is good, something is beautiful, or it is something that makes people happy.

A:

Is your teacher an anti-Trumpist? If so, she is ironicing(反讽) him, that is, deliberately describing Trump's "dirty" language as extremely pure.
The lotus flower in China always represents purity and nobleness, because it "is out of silt but not stained, and is clear and not gaudy" (Zhou Dunyi[周敦颐] in the Northern Song Dynasty[北宋], "Why Do I Love Lotus"[《爱莲说》]). Another example is the Southern Song[南宋] poet Yang Wanli[杨万里] wrote in "Little Pond"[《小池》], "The little lotus just started to grow up, but dragonflies have long been on it"(小荷才露尖尖角，早有蜻蜓立上头). But Trump’s words are not like this. His words are very offensive and often slander others. In the eyes of the Chinese people, this is "the words of a despicable person" and is dirty. This is in sharp contrast to the purity of lotus.
Irony is a commonly used rhetoric. Its definition is "It is impossible to understand what it really wants to express purely literally, but in fact its original meaning is just the opposite of what it can understand literally, and it is usually necessary to understand its meaning from the context." , The students are late, if the teacher is angry, sometimes they will say "you came so early". If someone does something stupid, you can mock him: "You are so smart!"
Therefore, if your teacher doesn't like Trump, the meaning of "口吐莲花" here is likely to be closer to "spitting dung in the mouth"(满口喷粪) or "dirty mouth"(出口成脏).

