First of all let me be clear I didn't used this exploit..didn't came to know about it until now.
2nd yes the ban is valid and justifiable and I respect DE's decision.
3rd...I think if DE is planning to give a 2nd chance to players....this is now. Nope...don't lift the ban completely. Do suspend them but reduce the suspension time. At least reduce it for players who aren't extreme offenders and tried it out of curiosity only. 17 years is like telling these players to #*!% off. Players have learned their lesson I think and a decent but not outrageous suspension will do the job along with issue of an warning. You can use this time to do the damage control. I think increase in outrageous bans will result in snitch mentality among Warframe community which isn't good for surfacing further exploits.
But it is your decision to make not mine and I will respect your decision in the end DE.