Possible penalties for a man neglecting his registration requirement do include jail time and heavy fines, however, prosecutors must prove knowing and willful violation, which is practically only possible in cases of self-publicized neglect. The criminal law has not been enforced in decades.
Failures to register will have a hard time getting federal money for stuff like student loans, however.
Given the tactical uselessness of draftees, selective service will probably never be exercised again without a major cultural, political, and military reversal and overhaul, making the penalties for failing to report when your card is pulled pretty immaterial.
No, this isn't subjective. Its an egregious violation of freedom to have your agency removed to fight in a war where you are likely going to die. Equality in this case is removing the selective service requirement for men.
You are subjectively interpreting the word "equality" which is not always a positive concept. -5 = -5 just as much as 5=5. Conditions can suck equally for everyone; granting benefits in the form of exemptions from service to one class may increase the aggregate good, but it does not increase equality. It is an egregious violation of freedom to be coerced by the government. That agreed upon, when the coercion is applied in the same degree to everyone, including not at all (as you advocate), that's equality. That's just the definition of the word. Your point is clearly stated, that you don't think subjecting a NEW demographic to an unjust statute really counts as "progress," which is reasonable enough. However, equality is what equality is.