China is in bad shape economically, and they've seen deflation while the rest of the world has seen inflation.
Bike specifically, prices have been falling, inventory piling up.
Past performance is no sign of future performance, it would actually make sense to have more inducements this year if they're trying to move stock and stimulate demand.
Also with the global economy slowing down, we could expect shipping prices to come down, and a fair bit of the what you spend on aliexpress is actually shipping cost, because that "free shipping" isn't free, although part of it is often subsidized by Alibaba.
Either way, if you're looking at big ticket items, it's worth using the messaging app to see what the seller has to say, you may get a good deal, extra coupons & so on.