With the salary cap, free agency and parity being what they are today
No doubt this is part of the era difference, but I think how much this benefitted Montana vs. current day players is overstated. For one thing, it led to Montana's departure from the 49ers, since they were able to pay everyone on the team while keeping Young on the roster as a backup. Those 49ers also could not sign free agents like Moss and Revis to bolster their roster.
I think anyone alive during Montana's playing days can name his supporting cast on offense
I doubt anyone alive during Montana's playing days can name the offensive players on his first Super Bowl team. These were the other starters:
RB - Ricky Patton
FB - Earl Cooper
WR - Dwight Clark, Freddie Solomon
TE - Charle Young
LT - Dan Audick
LG - John Ayers
C - Fred Quillan
RG - Randy Cross
RT - Keith Fahnhorst
Not exactly household names known to fans everywhere. Maybe you were referring to his second Super Bowl team:
RB - Wendell Tyler
FB - Roger Craig (rookie year)
WR - Dwight Clark, Freddie Solomon
TE - Earl Cooper
LT - Bubba Paris
LG - John Ayers
C - Fred Quillan
RG - Randy Cross
RT - Keith Fahnhorst
Everyone knows Jerry Rice, of course, but many don't know that Montana's first two Super Bowls were before Rice was drafted. On his third Super Bowl team, he had Rice and Craig but do most people know that Mike Wilson was the other starting WR? That Ron Heller was the starting TE? That they had different starters at every OL position from the previous Super Bowl team?
The idea that Montana played all of his Super Bowl years with All Star offensive casts is wrong. Plain and simple.
Brady has made some marginal talent at WR look very decent.
Every great QB has done that. Montana did it with Clark, Solomon, John Taylor, and others.