A casual observer might believe that YouTube is a site all about cats, or video game highlights, or anti-vaccine rants, or possibly just a repository of late night talk show bits. But no: the true purpose, as with almost all of Google's products, is to sell you stuff. To that end, YouTube is acquiring a smaller, weaker video site that's all about selling you stuff, albeit in a more direct way.
SimSim is an Indian video service that looks a lot like TikTok, except it's transparently about influencers shilling for products directly to their audiences. It was founded just a couple of years ago in 2019, growing rapidly by focusing on a huge population of Hindi, Tamil, and Bengali speakers. YouTube's blog post says that SimSim will supplement its efforts to "help small businesses and retailers in India reach new customers in powerful ways."
In terms of format, SimSim has a lot in common with YouTube Shorts, which themselves are a fairly blatant ripoff of TikTok. It's not immediately clear if SimSim will remain an independent product or simply be folded into YouTube, with its technology possibly expanded beyond its current market. But for the moment the focus seems to be fairly limited to India.