I am incredibly grateful to you for such large and lengthy answers and for taking the time to write my huge text.
Yes, I found a list of planned things, but I think it's a little modest for such a game with such a large community. It's just that when I played the game, I would never say that this game is like an indie project. I can only say that the game looks unfinished and it lacks a bit of content. In addition, when I looked through the list of top-selling steam games, there was also 7 days. That is a very ambitious project
Yes, it is, and it is also almost finished. They have a plan, a small team, and it would probably be a bad move changing course so late in the development. Much better to add additional stuff on top as an expansion, DLC, or second iteration. This also helps modders, as they want a stable base game eventually so they don't need to adapt their mods all the time.
Per definition TFP is definitely indie, as they don't belong to one of the big publishers. But sure, they are definitely not a 1- or 2-man team that makes the game with money lent from their grandma

Will DLS appear in the game? Can't you just say a few words about what they might be or their guesses?
Do you mean DLC? I am just a player, not employed by TFP. I don't know their further plans and they have kept mostly silent about them, but I think they don't like DLCs very much. So I would bet my money on some free patches to supply stuff that is still promised from the kickstarter but missing and then 7D2D 2.
Are they going to finish the game? I really would not like, since the game is super interesting, to literally add a few necessary things and I can say that this is one of their best survival and zombie-themed games. In addition, the game has a high online, maybe if the online will grow with updates, they will change their plans a little?
They are going to finish the game. I would say many of us players would like them to continue indefinitely, but they need new sources of income and for the sake of the future console version there needs to be an end as well.
Once again, I thank you for your attention. I am ready to send you a small donation for the fact that you gave me time and answered all my questions well. Just tell me where I can do it.
No need. Forums are and should be free sources of information