One ought to to check out the offenses committed as well. These are no ordinary crimes. Public opinion matters. It's a large and extremely complex place and "system".
That feels very bad to me. If a retentionist country wants to hang people, it shouldn't add endless insecurity on top of the punishment.
Edit.: interesting that this is controversial enough to be downvoted. Remember Trump signing the death warrants of 13 federal death row inmates during the last 6 months of his presidency? Yeah, once you are legally condemned to death, your actual execution is a matter of electoral random walk, which is pretty nasty.
Tangentially, how should a country (read US) deal with terrorists (in the strictest possible sense of the word) who planned and carried out significantly impactful attacks against their citizens?
Its probably not being downvoted for that reason. Rather because you're just being plain wrong here.
How can you know? It is entirely possible that a change in policy will result in all of them hanging within a month. Once you are condemned to death, the only thing between you and the gallows is policy that can be unilaterally changed by whoever decides to carry out the executions or not. The court has spoken, you won't be sentenced again. You are a dead person walking and someone in the executive branch can always decide to let you actually hang. An election of a politician who wants to look tough on crime may result in precisely that.
Tangentially, more than half of the world abolished the death penalty even though terrorism does not spare them. Spain lets Basque butchers live behind bars, so does France with its jihadists.
It seems to me you dont have the faintest clue how the Indian justice system works, I'm not even sure you're aware that India does have law and order like a civilized democracy. It has major problems within it, but it's not entirely nonexistent.
About the second point, I'd just add again, that public opinion matters.
As far as public opinion goes, yes, it matters, but it may not be decisive. Quite a few European countries would probably re-introduce the death penalty if the question was left entirely to the population (via a referendum). I am sort-of glad that they don't go down this road; not even Ukraine sentences Russian war criminals to death.