STC series single chip makes digital tube brighter

The I/O port of the STC series microcontroller has a strong pull-up mode. What is the strong pull-up mode?
The I/O port of the STC microcontroller can be set to four modes: quasi-bidirectional port/weak pull-up, push-pull/strong pull-up, input/high impedance. When set to push-pull/strong pull-up, the current it can withstand is very large regardless of output 1 or 0.
The special function register (SFR) of the STC microcontroller adds PXM1 and PXM0 registers to the I/O port, and each port has such a pair. The working mode of the port can be selected by setting the value of PXM1:PXM0:
The definitions of PXM1 and PXM0 are as follows:
0 0 Quasi-bidirectional port (traditional IO)
0 1 Push-pull output (strong pull-up, current up to 20mA, use as little as possible)
1 0 Input only (high impedance)
1 1 Open drain, such as the traditional 8051 P0 port
The following takes the P1 port as an example:
The names of the mode configuration registers of the P1 port are P1M1 and P1M0, and the addresses are 91H and 92H respectively.
Example:

Whether it is assembly or C, the definition of registers is the same:
P1M1 equ 91H
P1M0 equ 92H
Then, there are the following statements in the program:
Assembly language:
mov p1m1,#00000000B
mov p1m0,#11111111B ; Set all p1 ports to strong pull-up mode
C language:
P1M0 = 0xC0;
P1M1 = 0xA0; //P1.7 open drain, P1.6 high impedance, P1.5 strong push-pull output, other quasi-bidirectional I/O ports.

Using this function, it is very easy to make the digital tube display brighter. In the past, I always thought about adding pull-up resistors or buying digital tubes with higher brightness. Now, I think it is great that I can do it with just a software setting. It is really cool!
(The microcontrollers I use are STC11F02E and STC12C5A60S2).

However, the teacher has two pieces of advice here:

1. Ants can drag things that are 100 times heavier than themselves, but they are still ants after all. It is obviously impossible to ask ants to pull a carriage. Therefore, the "strong" of strong pull is only relative. It is okay to pull a digital tube, but to pull devices such as relays, you still have to follow the standard circuit. You still have to add transistors when it is time. Don't be too greedy.

2. Once you set the I/O port to pull-up (push-pull) mode, you must not connect the wires of the two ports together, otherwise, once one pin outputs 1 and the other pin outputs 0, your port will be burned. If it is not set to pull-up mode, the I/O port will generally not be damaged.