I think until these are either integrated into ebikes or can work while being stashed inside the actual frame then they’ll only really deter the odd Gary who was walking past.
As said in the article, proper organised thieves will just belt the thing with a hammer to kill it or just sling it in the back of a van and Foxtrot Oscar regardless of the noise. I mean these are the kind of people that come tooled you with bolt croppers and power tools if they want to.
Maybe something that’s attached to a thunder-flash or stun grenade might work. But then there’s a legal aspect to that.
Or take a big dog to the shops with you each time and chain ‘Fluffy’ up to the bike.