Doesn't matter how much you sweat, it matters what you do with them after the workout. If you wash them or even just let them air out after use, it's not a problem. I have 15+ year old synthetic shirts which have been on dozens of 5+ hour mountain bike rides in 80-90 degree weather and they don't have any scent at all.

That's exactly what I do. Hang them up after riding (on a hanger in the garage) so they dry, then wash with normal detergent and sometimes maybe a bit of powdered OxyClean (sodium percarbonate).

I've had phenomenally gross post-ride jerseys (literally crusted with sweat), but doing this they don't get stinky. I agree that the key is to not let them stay wet and let bacteria grow in it. Get them dry fast, all is good.

Wash them with just soda crystals.

For maximum odor removal, soak in sodum percarbonate (most clothing seems to do fine with this, one or two that I've tried don't)

Aka: Oxiclean (TM) in North America.