Even Tata sky HD provide 1080i but other Dth provide 1080p
Uh-huh?!?
You do realise that even if that sounds to be the case..
...To be radically-honest: It's precisely the equivalent of upscaling.
The overwhelming-majority of the globe, DVB® or not — relies on the "i" format because it resource-optimises the damn bandwidth.
Simply put, the vast-majority of legitimate, publicly-accessible satellite feeds are themselves not uplinked in "p" format, even though the final-cut of any programming, or the processing of any LIVE programming might itself be in say.. "1080p", in that scenario.
As even if it were "1080p" through and through, the […] compression-techniqueS deployed to optimise the limited-space of bandwidth wouldn't leave any tangible distinction between "1080i" and "1080p", particularly to the naked, 20/20 eye. Except in name-only, 'course.
So.. Given that point having hopefully emphasised that myriad of factors at play: This is just the Consumerist perception of "4K", "8K", "16K" TVs — to be direct with allegories. Criticise TATA|sky™ all you want, but scientifically: This argument about "PQ" sounds limited.