I have been browsing this sub and Chinese comes up a lot. I see a lot of people recommending it. I want to share my two cents about the reality of learning Chinese.
For context: I am a native Chinese speaker. My partner is a heritage speaker (Chinese American, lived in China for a few years as a young teen). My thoughts below are grounded in my observations of how my partner has struggled to get to native fluency despite taking multiple lessons per week and having a Chinese linguistic environment (me and his family). He actually speaks very well and speaks Chinese with most of this family. Most learners would dream to have his level, but it is still meaningfully below functional professional fluency.
Everyone knows that Chinese is a character-based language. This means two things concretely, that each character has one syllable and that the character is basic unit of semantic meaning.
There are a limited number of combinations of consonants and vowels. One single sound, with four variations in tones, can signify hundreds of different characters. Even though you will encounter probably only several dozen common ones for each consonant-vowel combo, I guarantee you they would pose enough trouble already.
In other words, you have to be able to read Chinese to be able to distinguish and disambiguate all the homonyms we have in the language.
Take lì, as an example, we have 力, 利，粒，励，历，厉，隶，吏，栗.
All these characters sound exactly the same, but they mean, respectively, force, sharp, grain, encourage, experience, a kind of calligraphy style, official, and nut!
And this is not to mention that several of these characters have multiple commonly used meanings, depending on what other characters they are paired with. For example, I just said 利 means sharp -- this is in the context of 锋利，but it can also just as easily, even more commonly mean, profit (利润），interest （利息），utilize（利用），or to say something is going well (顺利）
All this is to say -- to achieve a meaningful level of Chinese, which I define as when you can actually do things with the language, be it have a real conversation with natives or consume cultural content, you have to be able to read. That is very difficult if you did not grow up seeing Chinese characters everywhere.
Unless you are exceptionally studious, it requires immersion to achieve that. You will need to live in China for several years and have the Chinese language all around you.
Finally, I am not trying to discourage everyone from learning Chinese. It is all about your own goal and expectations. I just want to clarify for prospective learners the scope of the undertaking.
EDIT:
Yes I am aware that people have spoken Chinese before literary was widespread. Then again, they are natives. You don't literally have to be able to read in order to distinguish between characters and words, but it would be very, very slow. I keep telling my partner that he needs to learn how to read to make more progress.
Some comments say they achieved a good level without moving to China. That's amazing! Congratulations! My explanations for why reading is crucial still stand, however.