There is no one-size-fits-all answer to this question, as the best platform for self-publishing will vary depending on your specific needs and goals. However, there are a few things to keep in mind when choosing a self-publishing platform.
First, consider the distribution channels that each platform offers. Make sure that the platform you choose can get your book into the hands of your target audience, whether that's through online retailers, bookstores, or other channels.
Second, think about the level of support and services that each platform provides. Some platforms offer more hand-holding and assistance than others, so consider what level of support you're looking for.
Finally, take a look at the cost of self-publishing on each platform. While most platforms allow you to keep a majority of the profits from your book sales, some do charge fees for things like listing your book, printing copies, or providing other services.
Ultimately, the best platform for self-publishing is the one that best meets your individual needs and goals.