The days of the Sony A-mount seem to be numbered - at least no SLTs appear on the English-language Sony.com pages any more - and as is well known, these had relied exclusively on the Sony A-mount. We remember: With the Sony A33 and A55, Sony introduced in 2010 the first cameras with semi-translucent mirror and with (a few years earlier taken over from Minolta) A-mount (SLT = Single Lens Translucent Mirror).
The semi-transparent mirror enabled electronic viewfinder systems and was seen as an intermediate step towards true mirrorless camera systems. In the last few years, the A-mount no longer played a decisive role for Sony, as Sony consistently and quite successfully implemented a mirrorless 1-mount strategy with the E-mount.
Sony A vs E-Mount
Due to Sony&s early concentration on the E-mount, it currently offers the most comprehensive mirrorless lens portfolio. But the competition in the form of Canon, Nikon, Panasonic and others is now also increasingly focusing on new mirrorless mounts, which, as more modern mounts with larger diameters, claim to enable better weight distribution of the glass elements and higher optical quality in the peripheral areas of the image. Whether larger mount diameters also offer advantages with sensor-stabilised cameras remains to be clarified ... In any case, the discussion of the advantages and disadvantages of the respective mounts is unlikely to become boring in the foreseeable future ...