use a led matrix 5x7 without driver chip?

Eric, where did you dig up these retro red bubble display? ...not that I will ask your for your's, but just like to know, because I resorted to NS board with 12 digit display!

Unfortunately, they are not red, were affordable, and working nicely: Retro Bubble Displays driven with 74HC595. Driving those directly - not using shift register - would be quite a number of GPIO pins to burn: 19 or 20 - exactly. PICO as 21... so it still would work.

With this large 7 segment display - 12 digits - you might even get in a

             _                    _
  |  _  |_| |_     |_|    _   _  |_ |   |
|_| |_|  _| |_ |_| | |   | | |_| |_ |_   .

8 resistors for the 7 segments and decimal point, and 12 digits...