I'm a native English speaker and taught myself Spanish. I focused heavily on grammar and verb conjugation such that I can explain verb tenses and their uses to someone else learning Spanish, yet I struggle to explain the same to an English learner. Either I didn't care enough to pay attention during my English courses or it's not taught.
To be fair, verb tenses in English are so easy compared to Spanish, it's not really the same required effort. As a native English speaker I found learning other languages a shock for how verbs change so dramatically according to context.
That’s the opposite of my experience with Spanish as I found verb conjugation super formulaic and easy. Regardless, what I meant is that I can explain when and why subjunctive is used in Spanish but struggle with this in English.
Maybe an unpopular opinion but I especially find verb tenses to be the least important part of learning and having a conversation. People will get the meaning if it was in the past or the future if you know words like yesterday/last week/tomorrow/next week.
Of course this is just a stepping stone, but why try to duplicate (or more) everything when what you most need is proper sentence structure in the present tense and vocabulary.
Although maybe there are some languages where this is not true, not the ones I studied (briefly or not). But in my experience it is also true for people speaking bad German (talking mostly self-taught or from basic courses, not for white collar jobs with large amounts of written text) - perfectly understandable, just no tenses.