The problem is that often-used files can span greater than the amount of the cache, and ISRT is not smart enough to detect thrashing and have a fallback retention/eviction policy. ISRT may work if you fit its intended usage profile. Pure SSD works every time.
ISRT does pep a system up, but IME, not nearly to 80% of having just an SSD. But, I have individual games and tests in VMs that get around half the max cache size, and I don't find programs to load much faster on a new SSD compared to a years-old HDD.
YMMV.
But there WAS a time when the opposite may have prevailed: smaller was faster. And I only vaguely recall that -- so I could also be wrong.
It's not that smaller is faster, by itself. It's that SLC is faster than MLC is faster than TLC. SLC happens be about half the capacity per die area of MLC, and a third of TLC. A 512GB SLC drive would be faster than a 512GB MLC drive, all else equal, but due to MLC meeting a performance, endurance, and cost sweet spot, it's much more than double the cost, as it is an ever-shrinking slice of the market (fairly stable in absolute terms, IIRC, but with MLC and TLC seeing increasing absolute demand).
BTW, "apps" did not start until windows 8.
Except that mobile basically didn't exist in the 90s, by which time the term was already in common use. Its common use
among regular people began with iOS, as Mac programs had been called apps for many years (it was not unique to Macs, just common with Macs).
