With the new macbooks, apple has tried to make data recover as hard as possible, especially with the new t12 chips. I am not sure if the ssd is encrypted but if you replace the ssd, the T12 chip finds out and doesn't power on or something like that
For gaming 16GB is enough. Personally I would use it for a few more months beofre upgrading. I am going to upgrade CPU and RAM in May 2020. Hopefully prices will be cheaper.