It seems like this interview has touched a nerve. One European MP has called for some kind of travel sanctions on Carlson.  The Guardian and Independent have both run sabotage pieces – citing everything from Tucker’s having interviewed someone about UFOs to his “years of anti-Ukraine vitriol”. The idea is to completely discredit Carlson in advance of the interview – and thus shut down the interview.
Carlson apparently incorrectly claimed that other Western journalists have not tried to interview Putin. The Kremlin has stated this is incorrect. The question then arises; why was Tucker Carlson granted an interview. The standard MSM response will be “because he is a Putin puppet”; for example, the Guardian notes he: “has drawn accusations that he is acting as a propaganda tool for Putin”.
There is another reason. Look at this statement from the CNN’s Christiane Amanpour: “Does Tucker really think we journalists [notice the snide implication that Tucker is not a journalist] haven’t been trying to interview Putin every day since his full-scale invasion of Ukraine? It’s absurd – we’ll continue to ask for an interview just as we have for years now”. 
And this is the reason. There was no “full scale invasion of Ukraine”. This is the point made by Professor John Mearsheimer very convincingly. The forces which crossed into Ukraine in February 2022 were nowhere near big enough to have carried out an “invasion of Ukraine”. The force consisted of 190,000 troops; Ukraine’s army at that time was perhaps 300,000. The force was simply not big enough to invade and occupy Ukraine. This isn’t simply a mistake in military analysis. The whole point of calling it a “full-scale invasion” is to deny what it was – an attempt to protect the Russian speakers in Eastern Ukraine and an attempt to reverse the Maidan coup and put Ukraine back on the path it was before that coup, at least in relation to NATO membership. The Western media-political-corporate-military establishment has to deny that explanation because it is valid* and yet they have no intention of engaging with it. Russia’s legitimate security needs and the wishes of the minority population in Eastern Ukraine do not count for them. They have long ago been zeroed out. So the offer by Christiane Amanpour amounts to “why don’t you come on air and justify what you didn’t do but what our propaganda says you did”. It is a sort of double-bind (of the dizzying kind that Dostoevsky sometimes represents in his novels). I can completely see why the Kremlin has declined such offers. At the best Putin would have to spend the whole interview explaining why the premise of the question was wrong. And it is very unlikely he would be permitted to do this.
I’ve watched a couple of interviews recently when respected Western news anchors interviewed Russian analysts. These people are not even directly connected to the Kremlin. But in both cases the treatment was the same. One interview was by Piers Morgan  and the other by a leading anchor on Deutsche Welle. In both cases the interviewer clearly “had an agenda”; they more or less shouted at the Russian expert, hurling accusations at them, and in both cases blocked them from expressing their point of view. Perhaps they felt that was what their audience and regulators expected of them. But anyone looking to hear a Russian point of view was not well-served. There is every reason based on her comments above to believe that if Christiane Amanpour was granted an interview with Putin she would do something similar. Putin is a President; he has to consider the strategic impact of any interview he gives. He isn’t going to let himself be demeaned and shouted down or run the risk of that happening.
If Tucker Carlson allows Putin to explain his position, what he has done, and why, and what it would take for him to desist, that in itself will be a massive service to peace.
*- I mean the explanation is valid. That is not exactly the same as saying it ‘justifies’ the actions
- https://www.youtube.com/watch?v=HX2IRrPMNtw&ab_channel=TheHill [1.59]