The rumor mill never stops spinning and the latest murmurs suggest AMD may be working on a brand new entry-level Radeon RX 6300 desktop graphics card. While the announcement of new GPUs is never discouraged, the Radeon RX 6300 will belong to AMD's Navi 24 family of GPUs, which are famous or rather infamous for having several key handicaps, like low PCIe thoughput due to having four lanes (x4), no AV1 video decode and lack of any sort of encoder.
AMD brought the Navi 24 to the DIY market in the form of the RX 6500 XT and the card was widely criticized by reviewers due to the aforementioned limitations. I personally argued that the cut down 12CU variant in the form of the RX 6400 would have been a better DIY release as the low PCIe bandwidth wouldn't have bottlenecked a 6400 as much as it did to the 6500 XT. (Looks like AMD has listened).
So while you may be wondering why an even slower card in the form of the RX 6300 could be a reason for worry, the answer lies in its mobile counterpart, the RX 6300M, which only comes with 2GB of VRAM across a 32-bit memory interface. If AMD decides to go this route for the desktop 6300 too, ie, a RX 6300 with only 2GB of memory, then once more we could have a repeat of the 6500 XT situation, or potentially worse, when running the card on a PCIe 3.0 or older system.
Two gigs of buffer is too low nowadays and textures, among other things, eat it up quickly and that, paired with the low x4 PCIe bandwidth could severely affect the card's performance. Fortunately though, the card is rumored to be an OEM only option which means it may not have to bear the brunt of most reviewers, though it would likely still be a bad card offered by OEMs.
However, we must also remember that AMD has been offering different specifications for its laptop and desktops SKUs for its 6000 series GPUs, and hence the new card could also come with 4GB of VRAM, which in turn will make the RX 6300 a very potent entry-level GPU solution if priced appropriately.