" causes a specific reaction with the Tamiya acrylics solvent, and actually turns the paint into a lacquer "

No  ,

the lacquer thinner is used as a reducer to modify dry time and allow the coating to level and bond to the substrate while wet .

The difference between  lacquer acrylics and those that aren't is the formulation of the acrylic resin binder .

Here : https://coatings.specialchem.com/selection-guide/acrylic-resins-for-coatings

Some of the acrylic resins are compatible with alcohols and ketones  ( isopropyl  , ethanol etc  / acetone , butanone (MEK) etc )

and others will have a negative reaction .

The AK 3rd Gen will turn to snot immediately with the addition of alcohol  , Vallejo will coagulate with ketones .

The term  lacquer thinner  is like the word  beer .

It doesn't tell you if it used lager or ale yeast  , what type of grain was fermented , if hops was added ...

Brands like  Kleen Strip , like you find at Home Depot , contain both alcohol and acetone along with a mix of other solvents .

The paint manufacturers concoct their own " lacquer thinners " to work best with the type of acrylic resin they are utilizing .

As you know  , the MSDS will show you what is in them . Some will contain only alcohols and others will include ketones .

All chosen to provide the best overall performance of the resin at hand .

But , another formulation of reducer ( lacquer thinner ) may improve performance depending on the environment and substrate the coating is applied to .

It just has to be compatible with the acrylic resin being applied .

And , yeah  , solvent based coatings have better adhesion on polystyrene since they attack the surface to create a better bond .