I’m just going to have to quote @kaysik on this:
It’s worth remembering that even native Mandarin speakers spend years refining their tone usage, starting in preschool and continuing through formal education, because tones are fundamental to meaning in Chinese, not just an extra feature. While tones might feel arbitrary if you’re only using simple, predictable sentence structures, Chinese is highly flexible. Sentence patterns and expressions vary widely across regions, and tones help you interpret meaning accurately in those less predictable contexts. [comprenders.com] [3isolution.org]
You’re right that people can often get by without perfect tones in casual conversation. Many speakers from non-Mandarin regions do this too. But as topics get more complex, tones become part of the word itself, and mastering them really does take your language skills much further. [traverse.link]
What you’re describing, finding tone marks hard to use but doing better through listening and mimicking, is actually very common. Research shows that some learners (and even people from tonal-language backgrounds) struggle with tone literacy, meaning reading tone marks and producing them accurately, while oral practice tends to be more effective for acquisition. In fact, studies suggest that perceptual and oral training, listening and repeating, outperform tone mark drills for most learners. [frontiersin.org], [cambridge.org] [journals.sagepub.com]
So if you’re already good at recognizing tones by ear, oral learning is the way to go. If mimicking feels hard or isn’t working sometimes, adding structured tone drills from books can help. Even something simple like reading a new word aloud several times when you first learn it can build muscle memory over time. [benjamins.com]
To actually respond to your original post, given that, even though this website does have audio incorporated with the words, having the tones is still a really useful guide, especially for people who don’t come from a tonal-language background or who may not have as many opportunities to converse with others due to time, environment, etc.