The Quake3e engine you use is based on IOQuake3, and the IOQuake3 developers cut out the g_botsFile function because of its unstable behavior in different situations. People used it ineptly, which is why errors often occurred.

In general, there are both ready-made engines and open source code. If someone wants to use a new engine with this function, they will have to correct the code and then compile it into the engine themselves. But I doubt that there will be many such enthusiasts)

But for risk-taking guys, the path is something like this:

To re-enable the g_botsFile CVar in the Quake3e engine, you need to enable botlib support:

1. Classic Makefile
Create or edit the Makefile.local file in the root of the repository and add:

BUILD_BOTLIB = 1

make clean
make

2. CMake

mkdir build && cd build
cmake .. -DBUILD_BOTLIB=ON
make

3. Visual Studio (Windows)
Open the Quake3e.sln solution, locate the botlib project, and enable its build for your desired configuration (Debug/Release). Rebuild the solution.

After building with botlib enabled, you can set in the console:

g_botsFile "scripts/bots.txt"