I used to work with Thomas Bushnell, who was deeply involved with the Hurd at the beginning. His claim was that microkernels offered theoretical advantages on paper, but practical complications that Stallman seriously underestimated.
He says that he had originally suggested taking a BSD kernel and rewriting all of the (then) legally risky bits, and he still believes that this would have been straightforward, and if they had followed that route then Linux would not have stolen their thunder. But he let Stallman argue him out of it, and that was a mistake.
He says that he had originally suggested taking a BSD kernel and rewriting all of the (then) legally risky bits, and he still believes that this would have been straightforward, and if they had followed that route then Linux would not have stolen their thunder. But he let Stallman argue him out of it, and that was a mistake.