No, the episode pretty firmly establishes that all resequencings of DNA -- in other words, all acts of genetic engineering -- have been banned.
But you saw the quotes - they don't cover all the bases, and other evidence exists to indicate that the ban is not absolute.
One shouldn't breed supermen, but one can certainly manipulate a person's genome back and forth as long as the effect is purely therapeutic. Dr. Crusher redid the genetic code of dozens of people, usually for the purpose of reversing an adverse change on it.
Certainly the plot of "Dr. Bashir, I Presume" did not affect the Star Trek that came after the episode: genetic manipulation for the benefit of the patient's health continued unabated. In VOY "Lineage", the EMH readily recommended genetic modification for Miral Paris' back problems, and had no legal objection to the further genetic changes B'Elanna wanted to perform on her, either.
This would all be consistent if the ban were only there to block future Khans. And "Dr. Bashir, I Presume" is consistent with that.
Timo Saloniemi