Lilly, your understanding of presbyteral ordination is severely flawed.
Once ordained a priest, that person is a priest forever; nothing can withdraw that.
A suspended priest sins by performing the sacraments. (The sin is disobedience.)
A suspended bishop sins by acting as a bishop, but is still a bishop. (again, disobedience)
The SSPX are ALL clerics (subdeacons, deacons, priests, and the 4 bishops), and there are no laymen in the SSPX.
Lay Adherents to the SSPX cult* are not members of the SSPX. Nor, per the rules of the SSPX, can they be, except by ordination.
The lay adherents sometimes hold extremely schismatic views, and many hold mildly schismatic views; most of the SSPX themselves can be seen as schismatic, even tho, formally, they are not in a state of schism. (In short, they are approaching the line of schism, but are not quite over it.)
The big difference between “Traditionalist Catholic” and “SSPX Adherent” is a fine one; many SSPX adherents have no problem attending FSSP or ICRSS liturgies, or even Eastern Catholic Church parishes. Many Traditionalist Catholics feel the same, but will not go to SSPX liturgies due to the suspensions and irregular status. Mainstream Roman Catholics accept the Ordinary Form, as do a significant fraction of Traditionalists, but very few SSPX Adherents do.
*cult, in the technical sense, is a distinguishable body of followers with a common practice. Some Catholic groups are termed cults as well, without prejudice to their licity nor validity, including those who practice certain devotions to specific saints.