>>281731888
I think it's an amalgamation of different reasons, really. While indeed time is a contributing factor. We can only speculate and the only one that can confirm the true reason is the mangaka themselves.
But you are correct in that blaming the tools is wrong. It is about individual output rather than a blanket effect.
>>281732190
>>281732450
>Dissing THE Hagiwara
He was making the best art in the industry with ancient versions of Photoshop before you were even in diapers!