The name William Shakespeare appeared on title pages of plays and poems because an author’s name was needed, the true author had to remain hidden for reasons I’ve given in dozens of essays here, a genuine pseudonym wouldn’t have worked for long for such popular works in such a small community, and William of Stratford perfectly fit the bill for such a ploy. This is hardly an unusual maneuver for writers who wish for any number of reasons to hide their identities. Many examples can be found in the recent book “Anonymity” by John Mullan.

“Most likely known as a play broker”? Known by whom? Where is the evidence anyone ever saw William as a play broker? There isn’t any. Nor would we expect there to be any since the Lord Chamberlain’s Men would have made it impossible for William to get his hands on a manuscript. Play manuscripts were immensely valuable. They belonged to the Company and the actors were a tough lot, not to be messed with.

The Queen did protect Oxford, but only in ways that allowed her to control him. Twice when he was in real trouble financially she stepped in, once to give him an annuity that allowed him to maintain his status as an earl, a second time to get him married into a family with means to support his title. The monarch who truly did support him was King James, who saw to it that he got the stewardship of the Forest of Waltham, where, under the King’s own protection, he was as protected as he could possibly have been from the hatred of his two worst enemies, Henry Howard and Robert Cecil. All of which is explained in detail in numerous essays on this site.

Your final question is well put. Yes, by making it official that the plays were written by a provincial commoner who could not possibly have known the high level individuals caricatured by Shakespeare, any effort to see the plays as commentaries on them or the Court was rendered fruitless (they hoped). Most “authorities” probably knew full well who was actually doing the writing, but the name on the title pages allowed them to ignore the issue. Since Oxford outranked his enemies, their only recourse would have been to have him murdered. By removing himself to the forest where he was protected, he managed to keep himself safe for as long as he lived, and his papers safe as long as his patrons, the Pembrokes, remained in power.

In a related question, you have stated the need for secrecy because of the oppressive nature of the state. My first question is, if Oxford was a favorite of the Queen, why wouldn’t she have protected him?

Secondly, if the authorities thought the plays were written by William Shaksper, the play broker, why didn’t they go after him like they did with Marlowe? Was it because, thinking that the plays were written by a commoner, they couldn’t see or didn’t look to see that the satire was directed at them?