4 digit 7-segment display
The key point is that if you do that, you're doing it wrong.

Typically a multi digit display is time multiplexed, such that you use a common set of segment lines to activate the pattern on each digit in turn, therefore at any one time only at most 7 (or 8 counting the decimal point) segments should actually be on.

Then in terms of the common connection which selects a given digit, this will indeed typically have to source or sink more current than an MCU I/O pin is typically rated to handle, so it's best if the common connection is driven by an external transistor or FET.

Other options of course include mutli-digit LED display drivers, or lower power display technologies like LCDs.

That said, if a software bug briefly means everything is on, chances are the chip will survive.  But hopefully this only happens to "engineering units" - you do want to make sure that production units don't suffer this at some point in the programming process or something like that (though that's not all that likely, as typically all I/Os become inputs with at most a weak pullup).