What differentiates Judo and BJJ attitude and mindset? Same Jacket, different rules and mentality.
Judo training will vastly improve your Jiu-Jitsu and vice versa. However, both sports have their own set of rules and have different goals and mindset. For example, in Judo the match is won by ippon when the opponent is thrown flat on their back or when pinned on the ground for 20 seconds. For those reasons, BJJ players need to know how to “modify” and adapt Judo accordingly for BJJ.
Generally speaking, Judo just like Wrestling which is focused more on the stand up part, is much more aggressive and fast paced than BJJ. If you watch two BJJ players who do not have much stand up experience and they start the match standing, it looks very different than a Judo or wrestling match. In a BJJ match, it is getting rarer to see BJJ players actively work for a takedown. It is more like one or both both players can’t wait to go to the ground so they can start working on their strong points.
In Judo it is the exact opposite, They usually put all their effort into the throw and want to avoid the ground.
BJJ nowadays is more of a flow while Judo is in your face.
A good analogy is this meme:
Here is a great documentary about Judo mentality featuring Argentinian/Spanish Judoka Tomas Morales.