The main dangers with unprotected cells are:
Shortcircuit: when there is a low resistance path between both battery terminals, for example if both ends are touched simultaneously by your keys. In a flashlight or any device that doesn’t happen because there is at least one component which spends the electrical energy, in this case the driver and LED, thus the electrical current is limited as it must do work to reach the other terminal.
Underdischarge: Below some voltage the Li-Ion cell is damaged, below some lower voltage the cell will start growing dendrites that will cause an shortcircuit when the cell is changed again. If the flashlight is turned on accidentally and forgotten for days or months the circuits may keep drawing a small current which eventually would empty the cell. Also flashlights with electronic switch will consume a very small current while turned off (parasitic drain), that could take months or years but it will eventually deplete the cell, this can be prevented by unscrewing the tailcap a bit before storing the flashlight so the circuit is interrupted. The lowest safe voltage is between 2.0V - 2.5V, flashlights with LVP typically shutdown at 2.8V to be in the safe side, but it’s not always effective to prevent parasitic drain.
The issue with Liitokala is that they were caught employing deceptive advertisment in the past, for example selling Liitokala 30Q, which was actually a cheaper cell with less CDR, as Samsung 30Q, so the community doesn’t trust them much when it comes to 18650 cells. Vapcell is more expensive but at least they are selling what they promised, when tested they always come within the expected specs, they also get some early access to new cells compared to other vendors, they certainly have some good contacts.
Here is a thread about the Liitokala issue: Massive fraud on 18650s in the Littokala Aliexpress stores!
But if you brought their batteries recently and they served you well for your needs I think it’ s ok to continue buying them, just don’t expect them to fully meet their specs.