No, a minor language change in a lease won't do it.
The terms of the lease is the key.
The terms of the lease is the key.
I hope you understand that the Supreme Court's ruling allows for a minor change on the language of leases of public property, and the lessee (tenant) will be able to ban carrying firearms.
What will be interesting is that changing the language has other significant ramifications beyond the firearms issues, and it remains to be seen if the parties to the lease are going to be willing to make the accommodations required by the change in lease language.