fix: move from symbols to private methods

[wraithgar]

Also reverted an Object.create(null) to {}

[wraithgar]

cc @H4ad

[H4ad]

For performance, the fastest way of creating a object is like this:

https://github.com/RafaelGSS/nodejs-bench-operations/blob/main/bench/object-creation.js#L5-L6

Ref: https://github.com/RafaelGSS/nodejs-bench-operations/blob/main/RESULTS-v19.md#object-creation

But is not that critical so I don't think is a problem in any case.

[wraithgar]

Yeah again we need to balance performance with developer experience. This module is called maybe 20,000 times even on the largest benchmark install. Performance is important but it is not the bottleneck of a typical install.