So the jury instructions would be pretty powerful if the judge said, "You should consider the lack of bodycam footage as beneficial to the Defendant. You may reasonably find that the accused's testimony is more credible than the officer's during those 17 minutes."
True, but not the issue here.
> A juror is free to infer that you are guilty when you plead the fifth,
No, they aren't, which is why:
(1) If the trial judge decides before the case goes to the jury that a reasonable jury could not convict the defendant without making such a prohibited inference, the judge can dismiss the case, either in response to a defense motion or on their own, without even sending it to the jury,
(2) If the trial judge makes the same determination after the jury returns a conviction, the judge can toss the verdict and and acquit the defendant (which they could not do with a jury acquittal), and
(3) If an appeals court reaches the same decision after the trial judge has accepted the jury verdict and entered a conviction, the appeals court can reverse the conviction (which they could not do for an acquittal.)
Criminal acquittals are a constitutional special case of jury freedom in the US, as a special protection against imposition of criminal punishment by the government. The freedom juries have to ignore the law and facts and acquit because they feel like it in criminal cases is neither symmetrically reflected in a similar freedom to criminally convict, nor manifest, in either direction, in civil cases.
> "A juror is free to infer that you are guilty when you plead the fifth"
Indeed, but they are _not_ supposed to do so only because you plead the fifth, but presumably because of other evidence. In a civil trial, AFAIK that is not the case, the jury can infer you are guilty because you did not testify in your defense.