This is similar to how I feel about getting versus not getting a Leica SL2. Each SL lens can set you back $5000+.
When I had the SL, I had both the 24-90 and 90-280 lenses for it. Quite a lot of money! What I used on the SL the vast majority of the time was a small selection of my favorite R system prime lenses. (Note that the current prime lenses for the SL hadn't even come out yet, other than the 50mm.) Even though even the zoom lenses were at least the equal of those R system lenses (and usually superior performers), the SL series zooms' imaging was not wholly, noticeably, indefatigably superior to what the Leica R prime lenses could produce.
However, the difference between using the SL with its native lenses and using the Leica R and M lenses is much smaller than using, say, a Hasselblad 907x with a native XCD 45P lens vs a Summilux-R 50mm f/1.4 lens.
First off, by definition, "getting the most out of a particular camera and sensor" is impossible if you are constrained to not using the full format of that camera's sensor. Even though I can use many of my Leica R and M lenses on the CFVII 50c sensor, most of them do exhibit some vignetting and corner edge degradation when used on the full 33x44 mm format frame, more so than when using the same lenses on any 24x36mm format.
The lack of lens profiling for the Leica lenses on the Hasselblad sensor also cuts back on the notion of "getting the most" out of it. Hasselblad supplies in Phocus (and through Adobe in Lightroom Classic) lens profiles for ALL the XCD lenses that corrects and optically matches the lens performance for the digital back's sensor perfectly. Leica's factory lens profiles are only available in Leica cameras (the ones available from Adobe are often, in my experience, overdone in various ways which makes me suspect they're NOT the same at all). Thus you have a situation that even on the cropped format of the larger sensor, you cannot fully optimize the results as well as Leica has for their own camera sensors.
On the 907x, I can use my old V system lenses. These cover a still larger format than the 33x44mm sensor, and while there are no lens profiles available for them, it's less a concern because the smaller format means you are capturing using primarily the better, central 2/3 of the lens image circle, nowhere near the zone of edge degradation. And you also know that for the most part, like Leica lenses, the Hasselblad Zeiss lenses are top notch performers even on the larger 56x56 format they were designed for.
The result of these things is that with the Leica SL, just like with the Leica CL, I could/can use Leica M and R lenses exclusively and feel confident that I am getting the most the camera and sensor can offer, if not necessarily the most that the complete set of camera/sensor and native lenses can. So while the native SL lenses can provide some additional increment of performance, the increment is mostly fairly small in practical terms and particular imaging/rendering qualities (and the intent/execution by the photographer) will outweigh the native lens superiority in many cases. I do this today with the CL and my remaining M and R lens kit: thus far, I see no real reason to re-invest in expensive SL or TL series lenses.
With the 907x, I know for a fact that I need the camera/sensor AND the XCD lenses in order to achieve the most that the body can produce, and that the V system lenses will also do an outstanding job—better than nearly anything else other than H system lenses—despite lacking profiling. And I know for a fact that the Leica lenses cannot match their performance, again despite the fact that they can produce some extremely excellent results.
I would not have bought the 907x if I could not also plan to purchase at least a couple of XCD lenses or if I didn't have already have some V system lenses to work with; I would not be satisfied. I know for a fact (having done it) that I can do this with the SL or CL utilizing only what I already have in M and R lenses.
G
