The 2021 "South Wave" in the Hindi market was a perfect storm of superior regional content meeting a digitally-hungry audience. While platforms like 123mkv highlighted a massive demand for South Indian stories, they underscored the urgent need for robust, affordable legal streaming alternatives—a shift that has since seen major players like Amazon Prime Video
Also, I need to bring to your notice that I couldn't find any data on "South Hindi movie 123mkv 2021". South Indian Cinema usually produces movies in their regional languages. Not in Hindi. If you provide more context I can make an better essay.
The year 2021 has been exciting for South Indian cinema, with several blockbuster releases that have gained widespread acclaim. On 123mkv, you can find a vast collection of South Hindi movies released in 2021, including: