The difference in tracking ability and high frequency detail is massive between elliptical and a microline stylus ... and you can have tapered/not rounded aluminum cantilevers with great results.
I have had boron cantilevers ... and for me, stylus cut is more important.
No It's not - tracking ability relates to effective mass (also to compliance and arm matching!) - back in the day, AT made some superb very fine 0.2mil eliptical styli.... which tracked superbly - they were on a beryllium cantilever from memory (AT22)
The width of the horizontal contact patch, is one variable that impacts on tracking ability - it needs to be narrow enough to fit into the higher frequency "wiggles" - the 0.2mil elipticals, have a narrower horizontal patch, than the coarser (cheaper) line contact types!
On the other hand, for a worn record (most!) - the contact patch area gets worn, degrading what can be extracted from the record, an extended vertical contact patch, distributes the pressure over a larger area, reducing the wear.
Also an extended vertical contact patch (ie: line contact needle design) - will often read past the wear zone inflicted by elipticals and conical styli - thereby tracing "fresh" / "virgin" vinyl - making it sound superior to an eliptical or conical reading the same record.
On a virgin brand new record, the horizontal width of the contact patch, determines its ability to extract higher frequency detail.... and the best elipticals are a match for the best line contact - they have the same horizontal contact patch width.
Yes I would always recommend a line contact over an eliptical.... (even a high quality one as described) - but it isn't because of absolute tracking ability!!
With a few exceptions (such as the AT22), exotic, low effective tip mass cantilevers, have always had line contact needles on them.... and until recently, most basic cantilevers (aluminium) were not fitted with the line contact needles... which then tends to obfuscate the seperation between cantilever and needle performance.
The best Aluminium cantilever I have seen (and measured) was the flagship Stanton/Pickering, which managed to keep effective mass low enough to achieve a resonance at circa 19kHz... the AT440MLa which also has a tapered aluminium cantilever, with line contact needle - tends to have resonance around the 14kHz to 16kHz area... which is a performance limiter.
The Shure V15V with the Beryllium tube cantilevers pushed the resonant frequency out beyond the audible range to 32kHz - allowing a very flat frequency response... The Dynavector Karat with its stubby 2mm ruby cantilever, pushed resonance out to 50Khz, and the Technics EPC100mk4 managed to use a Boron Tube cantilever of extremely low mass to decrease the tip mass further and push resonance out to 100kHz (!!!)
The otherwise excellent Jico SAS styli, although Boron (or saphire/ruby) rods, have due to their construction, relatively high effective tip mass - with my measurements on different samples showing the resonance at 14Khz to 16kHz - about the same as a decent tapered aluminium design like the AT440.
And yes this stuff is measurable, objective, not subjective...