Individual cameras can basically live forever. A well-kept dry plate camera from the 1860s or a 1960s SLR can still capture images here in 2020. But inevitably, any given camera tech slips off the cutting edge and slides into "vintage" as development stops. That moment may finally be on the horizon for the DSLR.
Rumors are bubbling up from the cameraverse that Canon's EOS 5D Mark IV, the camera juggernaut's affordable workhorse of a full-frame DSLR, will be the last of its breed. Released in 2016, the Mark IV is the most recent in Canon's line of full-frame DSLRs that dates back to 2005. It was (and is) popular with DSLR die-hards for it more manageable size (and lower price point) compared to Canon's full-frame flagship 1D line. Rumors of its death, while they don't indicated an imminent death of the DSLR, do represent a sea change.
DSLRs, which share the Single Lens Reflex design of their film-based SLR predecessors, have a host of advantages over smaller "mirrorless" cameras. Their optics allow the operator to see through the viewfinder and directly out the lens for a lagless, high-resolution, no-batteries-required alternative to mirrorless cameras' "electronic viewfinders" which replace an SLR's bulky optical mechanism with a tiny screen.
And camera bulk is under assault from every angle. On one side, smartphones are encroaching on dedicated cameras for everyday users, while the compactness and performance of highly capable full-frame cameras like the Sony Alpha a7 III are peeling away professionals who aren't purists when it comes to mirrors.
While cameras devoted to smaller sensors, like the Olympus OM-D line, are not finding success purely by virtue of their size, Canon's potential abandonment of the 5D line speaks to a waning demand for anything but the biggest sensor in the smallest package.
It'd would be premature to call the code on DSLRs right this second, as both Canon and Nikon have dropped professional-grade full-frame DSLRs this year. And whatever the future of the line, Canon will no doubt continue to pump out 5D Mark IVs so long as demand holds despite the camera's increasing age. Still, if the 5D is in fact dead, it's a harbinger of leaner times to come when it comes to up-to-date DSLRs. Though diehards will surely keep using them through then, and beyond.