The definition of lactic technology to me ultimately resides not in terminal pH, but in the degree of casein degradation before adding rennet, and also the amount of rennet added. It has to do with the core reason that casein micelles aggregate.
In full rennet, there is only a small amount of acid present before rennet add... usually no more than .18 TA (6.5 or higher). In semi-rennet/semi-lactic, there's a wide range, but usually rennet is added around 6.0-6.2, when there's a good deal of casein degradation. And the coagulation is a mixed type... part lactic, part rennet. Rennet is added in the right amount to ensure the initial set occurs at 5.2-5.4.
And then in full lactic, it's a straight shot, acid and culture texturization via exo polysaccharides makes for the set. Here, pH is key, because micellar aggregation depends very heavily on the acid developed.
TA by itself won't really reduce the amount of acid... it modifies the curve. You can still get to 4.6 with TA. You time the make, though, to drain higher than 4.8, say, 5.0, and then also use a semi-lactic approach.
It will be different, that's why you should do a blend meso/TA to increase flavor. End result is a more stable cheese, ages slower.