Public attitudes may be changing. At least for Federal cases, it is quite rare for a grand jury to return a "no bill" or refuse to indict. Presumably, because federal prosecutors normally have their ducks in a row and present a strong case, or if they don't have a strong case, they don't waste time even bringing it to a grand jury.
However, per Wikipedia, "Beginning in late 2025, legal observers documented a marked increase in no-bill decisions in federal cases, particularly in matters arising from protest-related activity."