I've never tried to learn Hungarian but as a casual traveller there I deeply appreciated the phonetic spelling. The Hungarian alphabet can be memorized in an hour or two and then you can immediately pronounce any written Hungarian word and be understood (terrible accent I'm sure but the locals will get it).
By comparison, I've lived in Vietnam for several years now. The grammar is very simple. Every word is one syllable. A lot of common words are made from compounds of basic words (long horn animal = rhino type thing) so you can make educated guesses once you've learned a few words.
The problem? Nobody, including even my close friends, partner, and coworkers, can understand anything that I say in Vietnamese. Anything more complicated than "thank you", "hello", and a handful of numbers. And I cannot understand them either. If I pronounce a word as written but get the tone very very slightly wrong, it seems 100% impossible for Vietnamese people to infer the word I meant to say. It's incredibly frustrating and I've started and given up learning Vietnamese many times. I've learned some basic grammar, I've learned enough words to string a few sentences together. But what use is that when I go into a market and order something basic like "ice" ("nuoc da" , or just "da") and nobody has a clue what I'm saying?
Every conversation where I try to learn a new word in Vietnamese turns into ten minutes of "no, you're still not saying it right, the tone rises and falls at the end", "no, too much rise, say it like this" over and over until I give up. And that's not even mentioning the accents, differences in tone, and entirely different words used for basic things between the north and south of the country. Or the fact that locals are not in any way interested in trying to help a foreigner speak their language.
Learning Vietnamese is the most frustrating thing I've ever attempted in my life. I'm good at learning things. I'm sure I could sit down for a few days and memorize a hundred irregular verb conjugations. But I can't overcome this problem. How can you learn a language that you can't pronounce or hear?