Welcome to the community. Fine-tuning does have its limitations. It’s still useful in some cases, but a lot of people are switching to embedding + completion… If you search around the forum, you should find some useful for posts.
Also, is my understanding correct that fine tuning can only be used on base models such as davinci, curies, and since they lack instruction, it’s hard to get good results with them? Versus using the embedding + completion approach, I get to use models like text-davinci-003, which has been instructed and allows me to build something closer in quality to GPT 3.5 more quickly.