Of course he was deserving his place in Liverpool before leaving. But Liverpool were ready to accept a favourable offer from Bayern Munich in the summer and they accepted the offer amounting to 41 million euros with bonuses. It is still good for Liverpool to sign a great player like Darwin Nunez. Now they have an amazing trio like Diaz-Nunez-Salah. If Nunez manages to adapt to the team in a short time I think this trio will destroy so many teams next season.
I think that in the end this is a transfer where all parties involved are happy now in the end and that's how it should be in my opinion. Mane did not really feel that he got the amount of appreciation that he deserved at Liverpool anymore. He was just as important as Mohamed Salah for their game but still there was no doubt that it was always Salah that was treated as the biggest start of the Liverpool team.
Bayern was looking for a transfer of a big player who could immediately help them to attack again for the Champions League title in the next season and Mane is probably one of the best candidates to do that.
I also think that Liverpool is happy now because they don't have to pay Mane's salary anymore and they already have signed Nunez for his replacement.
I think its a win win for both parties sealing Sadio Mane's transfer to Bayern Munich. Liverpool will be relieved of the cost of keeping both Mane and Salah high salaries and Bayern Munich on the other end finding a good replacement for departing Lewandoski who is on the verge of moving to FC Barcelona this summer with talks already progressing. Mane will be happy now where he will be paid better wages for the kind of effort he puts in the team something he was being deprived of at Liverpool