This is what the source 2 engine upgrade to Dota 2 in 2015 did. Therefore this is what a Csgo source 2 port would likely bring:
“MULTITHREADING & STREAMING -
Source 2 will use any available CPU cores to provide a smoother experience, removing many hitches during gameplay. Also, much of the game content can be streamed in the background while the game stays responsive. Animation, voice chat, music and more can continue while the game is loading.
ENHANCED PERFORMANCE -
Source 2 was built to support a wide range of hardware. Dota 2 in Source 2 runs better on older laptops, and at the same time further increases performance on current desktops. Though Dota 2 may not require all of the resources of a high end machine, Source 2 has been built to be capable of driving modern machines to their limits. It can use all of your CPU cores, your 64-bit OS and memory, and includes support for recent and upcoming graphics standards like Direct3D 11 and Vulkan as well as virtual reality if the game demands it. Performance will continue to improve during the beta as we optimize it for more PC configurations.
MORE RESPONSIVE INPUT -
One of the ways Source 2 directly improves gameplay is by reducing the latency between issuing a command and seeing your hero react to that command. Our redesigned input system now allows the server to process mouse clicks and key presses directly into visible actions more quickly than before.
Source 2 also includes new versions of our physics and cloth simulation engines which implement higher quality, more stable simulations. In the future, more advanced Source 2 cloth and physics simulation technology will be used to power Dota 2 Custom Games content.”