I assume the GP was asking if the 90 day rule was really important to uphold, or if the disclosure could just be delayed longer until the patch went out.
Well,expecting there to be a patch without the 90 day exploit exposure is very generous. The whole point of a 90-day (or any arbitrary stretch of time) deadline is that a lot of companies are funny when it comes to exploits. Security doesn't ever make a company money, it's a high cost that can only (at best) hope to prevent the company from having to make reparations after a breach, maybe lose a few customers. As such, many companies treat security reports with indifference and do nothing whatsoever about reported exploits until they're forced to. The only real way private researchers or security groups like Project Zero have to light a fire under the company concerning the exploit is to release the exploit to the public when it becomes clear that the company isn't going to fix the vulnerability on their own. At least now consumers are made aware of the exploit and can make an informed decision on a plan of action. 90 days, 180 days, a year... it doesn't matter because people would criticize the length of time no matter what it is.