The Rosenbergs were executed for espionage under the Espionage Act 1917, not for acting as unregistered foreign agents under FARA. They were exfiltrating classified nuclear secrets. This is an entirely different thing.

Unregistered foreign agents tend to receive a fine, if they are charged at all. Before the past decade even this was very rare, now maybe there is one per year. The maximum punishment is like 5 years in jail, and no one has ever been hung for this. The directive to conflate these only traces to Pam Bondi.

Most of your post is like this in that you speak authoritatively but fumble premises. For instance you clearly don't understand free speech law. Yelling fire in a crowded theatre IS protected speech. The Schenck case your quote comes from was overturned in Brandenberg 60 years ago and is considered a national judicial embarrassment.