I'd like to add a few more observations.
1. Mix Presets. For a moment let's put ourselves in VSL's position - or indeed in the position of pretty much any and every maker of virtual instruments.
If you want your product to have an immediate positive impact on new and prospective customers, you'll want to provide presets that have instant appeal; served up on a plate with no effort required by the customer. And it's long been an industry cliché that your up-front presets will need some beautiful reverb to ensure they have that immediate, irresistible and inspirational je ne sais quoi.
Moreover, the vast majority of prospective customers don't (yet) have the knowledge, experience, technical expertise, craft and skill-sets required to prepare their own fx, reverbs and configurations that can surpass the attractiveness of the maker's presets. So it's really no surprise to find that many if not most virtual instrument makers design their products with the majority very much in mind.
But potentially there's a serious downside to this marketing strategy. As Jordan Peterson said, "you don't get people to stand up on their own two feet and to adopt responsibility, if everything is given to them". Therefore, as the instrument maker, you must choose to what extent you want to perpetuate the myth that by buying and operating your ready-for-use products, your customers can automatically become succcessful music-makers; and, conversely, to what extent you develop your products and your relationship with your customers such that both you and they willingly engage in the long, intricate process of exploring, learning and improving design and use of your products.
In my opinion, VSL have struck an optimal balance in the very demanding ordeal of riding these two horses. Some customers may find the complexity of VSL's products to be puzzling or even annoying, whilst others may complain that not enough latitude or leeway is designed into their products for users' solutions. There is no way of pleasing the whole market in this particular field of endeavour.
2. Surround sound is not, I would submit, about to transform digitally-aided music-making into a new and higher stratum of artistic virtue. Recent history shows how few rock and pop bands made use of more than stereo for concerts and recordings (Pink Floyd being the most notable example). And in films, I recall seeing the first Star Wars in a central London cinema fitted out temporarily with very large surround sound speaker stacks, but can't bring to mind any other examples. I still recall Pink Floyd's Dark Side of the Moon concerts in London's Earl's Court Arena, München Olympic Stadium, and Wiener Staatsoper; mostly the surround sound was about special effects. Those were exciting, thrilling and lovely experiences for audiences, but I think very largely due to the novelty value of surround sound. I'm betting it won't become more commonplace - especially not for orchestral music.
There have long been ways of configuring Silent-Stage libraries to produce surround sound. But the fact remains: it didn't become a thing.
3. Silent Stage vs Synchron Stage A. I see no cause to lament VSL's change from recording samples in Silent Stage to Synchron Stage A. For one thing, as noted by VSL, musicians tend to enjoy the sound of their playing in Synchron Stage A. Having worked on a contract involving me in use of an anechoic chamber, I don't imagine that musicians found the experience of sample-recording in the Silent Stage to be particularly helpful, gratifying or even pleasant. I'm all for making things as pleasant and as natural as possible for the musicians who render the samples we use.
The highly professional recording techniques used in Synchron Stage A of course include use of close mics to provide as dry a sound as possible wherever required. The residual acoustic ambience of these close mics can hardly be regarded as any kind of impediment for the vast majority of use cases.
