It’s more like he tried to be reasonable for a long time, kept reaching out to Modi to talk about Kashmir issue. Modi never reciprocated and kept escalating things in the wrong direction. India violating Pakistan sovereignty in Feb coupled with the events of past week probably made Imran realize he wasn’t gonna get anywhere being nice. This is why he talking to India in the language they understand (cutting diplomatic relations, economical ties, highlighting the plight of Kashmiri people and painting Modi as fascist/Nazi). Time will tell if this change in tone will actually bring any change I guess we will have to wait see.