Well, ok. FL22 has no 2EHA which is plasticizer and used in most of antifreezes.
Plasticizer - a substance (typically a solvent) added to a synthetic resin to produce or promote plasticity and flexibility and to reduce brittleness.
With manufacturers using silicone gaskets now, they strongly recommend to use these new antifreeze.
This is why on Mazda coolant reservoir you see FL22 printed in plastic. So, you don't put anything else and don't damage your engine.
I was watching a video on youtube - a guy replacing coolant in his Mazda3. "...I just bought these 2 Prestone coolant jags. Look how nice and light this fresh antifreeze looks. the old one is so dark..." And I think... dummy. It should be dark.