Yes and no.
No question that if you like the way you train more, you will train harder, be more focused and stick to the plan for longer. It will likely cause a smaller stress response too.
HOWEVER it cannot change physiological rules.
While some people CAN tolerate more volume (some gaining more when volume is higher)… HIGHER volume is relative and there is a limit to how much one can do/add without starting to hurt gains (mostly when they are natural).
The Best Damn Workout is on the extreme low end of the volume scale. Hard to do less volume than that. So it i definitely possible to do more volume and be capable of adapting positively and growing.
And you are right: if volume goes up, frequency must go down. Frequency both in terms of the number of sessions per week and how often you hit a certain muscle. You understand part of the concept when you talked about training a muscle once every 5 to 7 days but I’m not sure that you understand that if you use a high volume approach you will have to decrease the total number of sessions per week (normally to 4-5). Volume has a systemic effect so you can’t just decide to keep training 6 or even 7 days a week, with high volume, and recover properly as a natural.
Furthermore research is pretty clear that for maximal gains you should hit a muscle to some extent at least twice per week. For 2Bs the ideal split is as follow:
LOWER BODY (quads emphasis)
SHOULDERS/TRAPS & REAR DELTS
LOWER BODY (posterior chain emphasis… must include a deadlift variation)
With tthat split everything gets hit to some extent at least twice per week.
Chest has its own day and is also receiving some stimulation on shoulder day if you do overhead pressing.
Back has its own day and also receive some stimulation from deadlifting on posterior chain day and also on shoulder day when working rear delts and traps
Legs have two days, even though one is quads dominant and one is posterior chain dominant, both receive stimulation if you use mostly compound movements.
Biceps get trained directly on chest day and are also involved when pulling on back day
Triceps get training directly on back day but are also involved when pressing on chest day and shoulder day
Shoulders have their own day and are also involved on chest day.
But that is not a license to do crazy amounts of volume. How high can you go? I can’t say exactly as it will depend on each individual. But I would say around 22-26 sets in a workout at the most (not per body part, for the whole workout).