Hetzner can match OVH. To match their prices you need scale to build your own datacenters and servers. Small providers can't do that, they need to colocate and that'll usually be more expensive than owning your dc.
In addition to the video posted: Their DCs tend to be outside of cities (cheaper space), low density and single story (much easier to cool). If you buy cheap land and keep server density low, both building the dc as well as cooling is much cheaper (you can mostly use ambient air with lower grade fans).
Hetzner is also known to do everything in-house, slows them down building new dcs and expanding to new locations but keeps cost down and the company independent.
