What the hell are we doing as an industry? We have 20 cores per CPU and enough RAM to fit the entire human civilization's knowledge in text form in everyone's pocket, but we can't scroll a webpage with animations without stuttering?
It would be easy to add 20% of time and budget to a project and just let your developers work on bugfixes and improvements. Maybe even let your dev team interview a customer or two to truly understand what matters to them. But that's considered too expensive. (even though some SaaS have 90%+ profit margins)
As long as your tool demo works slickly on the highest performance Macbooks used by the execs you're trying to sell to, performance isn't a factor.