Well, there are a number of factors that give me pause about the HQ-16 moving forward. Main one is actually the range. The 40km is for aircraft, but its max range against cruise missiles is said to be as low as 18km...mind you that is against sea skimming missiles... Against brahmos, that may not be enough reaction time. One can say CAMM-ER is 45km...but in reality its "45km +". The standard CAMM has a stated range of 25km+ and has been tested to ranged of 60km...that tells me that CAMM-ER has a range much in excess of 45km and could be anywhere from 75-100km+ in actual max range. Beyond this CAMM and CAMM-ER were designed to intercept supersonic missiles. If you look a bit into Sky Saber (AKA Land Ceptor), it is designed to target stealth and supersonic cruise missiles). It is a far newer system from a very well known and reliable company when it comes to air defense systems (MBDA). AND YES, there is an added confidence in the notion of an active seeker over a SARH seeker, but that is not an end all issue.
Now that is not to say that HQ-16 is bad, but it was not designed for missiles like Brahmos (CAMM-ER literally was designed for that exact role). Newer versions of HQ-16 may address these issues and in fact, by all reports, they do, BUT PN doesnt have those variants yet, in the future, maybe they will be available, but those are further off than MILDAS for Jinnah or Babur, which im fairly certain is in the works. It is not at all the same issue as upgrading the F-22P. For one, the cost of removing FM-90 and adding the infrastructure for a VLS, changing the radars and combat management system all together cost more than the F-22P itself. Baburs wont need all that. It has all the infrastructure in place, wont need updated electronics or radars, it would be the cost of the VLS and manpower to install. Likely because the footprint of the GWS.35 is so small, you may only get 8-12 cells instead of 16,but quad packed in MILDAS, you would field 32-48 missiles instead of 16 (a good trade off).