Here's a breakdown of what transpired regarding the "drama"
He's drafted 9th overall in 2018, Kakko is drafted 2nd overall in 2019. Kravtsov came to America months early and did a lot of work in learning English (you'll see in his interviews how great his English is) and went above & beyond what's typically expected of a European prospect. In the 2019 training camp all of the Rangers beat reporters, front office, etc are reporting that Kravtsov was the stand out player of camp, totally outshining the hyped 2nd overall Kakko. He was far and away the most dominant player in that entire camp, and then in that 2019 preseason Kravtsov goes on to outscore not only Kakko, but also Zibanejad, Kreider, Strome, Chytil & Fox.
He's then cut from the team in favor of Kakko, who goes on to be the statistically worst player in the entire NHL that season. Kakko started his career stapled to the top 6 & PP1, handed every opportunity in the world but completely squandered it. Meanwhile Kravtsov reports to Hartford, after some time he decides to exercise his European Assignment Clause, something that was literally negotiated into his contract and completely within his rights to exercise. It's a very common thing for European players to do, even ones who aren't nearly as highly touted as Kravtsov was. The same season, but without even reporting to Hartford; Tarmo Reunanen exercised his European Assignment Clause as well. But Chris Drury, at the time GM of the Hartford Wolfpack; singles out Kravtsov when he's saying goodbye to his teammates and publicly yells at him, reaming him out & calling him a quitter in front of the team.
In 2020 during the bubble, the Rangers who didn't have much depth and wouldn't have made the playoffs if it weren't for the play in round expanding the teams who were in; asked if he wanted to come back over to play. Kravtsov skips his sisters wedding and hops on the first plane out for the opportunity to play, but the team opts not to play him a single game.
In 2021 the Rangers trade Buchnevich for Blais & a 2nd rd pick, with Drury citing the reasoning being to give Kakko & Kravtsov more minutes. Drury tells Kravtsov to skip prospect camp all together and report straight to the main team. Kravtsov plays well in the preseason once again and Drury in a bizarre move, does not invite him to the team building event in Rhode Island. Kravtsov once again does not make the team, and the entire fanbase is shocked and outraged at this. They opted to have the likes of Hunt, Hajek & Gauthier on the team instead. Hajek meant they were carrying 8 defensemen which was a very uncommon thing to do, especially when the other option would be carrying the standard number for each position including your 9th overall pick instead. This time Kravtsov does not report to Hartford, Drury then agrees to loan Kravtsov to Traktor of the KHL.
Kravtsov once again has a season that compares favorably to the likes of Panarin, Buchnevich, Kuznetsov, Tarasenko; including his signature dominant playoff performance which has become an annual tradition. Throughout the season he's in contact with the Rangers front office and they agree to try it again.
Kravtsov comes to camp early before anyone else to get a head start, this time making the team as the 2RW. He gets injured and when he comes back is now all of a sudden a 4th liner/healthy scratch even though his last game was as 2RW. He was healthy scratched for long stretches of games and Gallant would cite "Can't change things after a win" but when Kravtsov did play and they won, he would still be healthy scratched the very next game, all the time. When he did get to play Gallant would bench him for essentially the entire third period of games. When Kravtsov was on PP2 he would get 10 seconds and then he would sprint to the bench with about 20 seconds left in the PP to get Trouba out there, this happened every shift he's had on the PP for some reason. He would sprint to the bench while they had possession in the offensive zone, this was some strange demand Gallant had of him.
He was the first player on the ice at practically every single practise this season, often 10+ minutes before anyone else was even there. He always attended the optional skates, and did everything that was asked of him but was routinely the odd one out in favor of horrible players like Jake Leshyshyn.
Any honest person would say there is fault on both sides. I think that if we hadn't won the draft lottery in back to back years (Kakko/Laf) there would be widespread outrage from our fanbase for this treatment of a top 10 pick. If you go back and read GDT's from his 20 game NHL stint the 2020-21 season you'll see all of the Ranger fans fawning over him and saying that he was the best rookie Ranger they had ever seen, how they wish Laf & Kakko looked like him, and that he was better than Kovalev. He was routinely voted one of the top 3 starts practically every single game. But then they developed a vendetta against him because of the drama and now many engage in revisionist history claiming that he wasn't good.
Drury & Gallant have a type in players and they love the guys who are more than the sum of their parts, who lack the tools but play an honest game or whatever platitude you want to use. Kravtsov came in as a flashy, confident Russian kid who wasn't intimidated by the organization and stood up for himself when he felt he was mistreated and exercised a mutually agreed upon clause in his contract when they thought he wouldn't. I think Drury has had a vendetta against him ever since.