In what countries were the exams only once a year? When I grew up in the 90s in Sweden we would have tests and exams frequently, usually at the end of each module. This continued all the way through university. I think we had 3 separate exams for the first math course (which lasted a quarter of a year, so roughly one exam per month).
(Though they didn't give formal grades for the first several years of elementary school, which I'm not sure was a good idea.)
In the UK. In high school (age ~11 to 16) the only exams that mattered were SATs at ages 7, 11 and 14 (though I just checked and apparently they've scrapped the 14 year old ones for some reason), and GCSEs at 16. After that you have A-levels for two years (age 17 and 18) where IIRC it was just one big group of exams at the end of each year, and then university where I guess maybe it varies but at least at Cambridge it was one big group of 3-hour long exams at the end of each year.
Though Cambridge does have "tutorials" which are 1:2 tutoring sessions where you probably couldn't completely rely on AI.
Your way definitely sounds better to me.
In Poland, that's how it worked at unis. We had a lot of subjects where we had only one big exam at the end and your grade depended on it.
Before uni though, we would get a grade or two every week, be it from short tests, classwork, homework or exams.