I suspect the IRS ruling won't be the end of it. A collective somewhere will legally challenge the IRS's position in court, and then a court will have a final say on the issue.
That said, the IRS position seems sound. The IRS determined that NIL collectives, unlike traditional nonprofit organizations, do not serve a charitable purpose or provide a public benefit. Therefore, they do not qualify for tax-exempt status under the Internal Revenue Code.
Collectives may now be subject to reporting and compliance requirements that come with being taxable entities. That could deter the influence they wield with NIL money. Maybe the usual offenders will just go back to brown papers sacks filled with cash, and it will be business as usual again.