Even if trads are right and the NO is everything they say it is, the NO form, matter, and intention at baptism are all fine. Yes, the same is true of a Lutheran baptism. I am not aware that the Church has ever said it wasn't. Baptisms can be validly performed by pagans if the simply intend to do what the Church does.
And, although I don't think a presumption of invalidity is warranted on the part of the SSPX, I can see why they would be more likely to conditionally administer conformation than baptism. Confirmation is much easier to screw up.
I understand what you mean and agree that a blanket presumption of invalidity is not warranted.
Although revolutionary chaos reigns now, and some of the lunatic clerics in the Novus Ordo do not use the form for Baptism but instead they make changes to it which according the the theology manuals would be invalidating. Sometimes they do not even pour the water over the forehead whilst saying their "form".
They also sometimes make statements during the baptismal ceremonies that manifest that they do not intend to do what the Church does.
The Protestants of earlier ages were better at sticking to the form than some of the Novus clerics are. In fact one could arguably be better off if they were baptised by an indifferent Jєω or non-believer in an emergency, than having the NO ceremony because genuine mistakes aside the common Jєω or non-believer would probably more faithfully stick to the form if it was presented to them than some of those Novus clerics of a certain bent.
However for those people who have been baptised in the NO Church I think that traditional priests know how to investigate and try to determine what course of action is required, if any. Most traditional priests would also have more than adequate solicitude for people who come to the from the Novus Wastelands.