The CTX is obviously capable of handling a broad range of frequencies. Wouldn't it be nice to see something like a Multi-IQ mode added. To be able to toggle between FBS and Multi-IQ would be something. I suspect that might not be possible without the kind of processing efficiency of modern chipsets, or for all I know maybe it is, but just a hypothetical "wouldn't it be nice" idea.
I'm not new to detecting, but I'm new to the CTX so I can't say with any authority that Minelab has shirked it's responsibility to update the CTX, but I would say that I find it hard to imagine they haven't learned many new things they could've done better software wise since 2012. At $2,500 making sure the CTX is the best it can possibly be should be a top priority even now in 2020, until such time as they replace it with something else. That aside, it still seems to be miles ahead in some respects. To me, it seems to have no competition for what it excels at other than the Whites V3i. I can see why they wouldn't want to fiddle much more with it.