How to make youtube download videos in HD when the player is less than 1280x720?

My video space for 740x446 desktops. The client wants to force youtube to download 720p videos there because it looks better.

Can this be done and how?

What I tried: Force youtube to run at 720p (deprecated / doesn't work)
https://developers.google.com/youtube/iframe_api_reference#Playback_quality

developers.google link says you can only offer non-forced quality. In this case, does it even make sense to suggest it? Is this proposal ever obeyed?

I would rather not use javascript unless needed.