You don’t carry a mobile phone? There is a plethora of apps/websites for various risk scores that take minimal time to use.
Paracetamol overdose. It is a time sensitive and common ED presentation that uses continuous variables to guide treatment decisisons in the form of a nomogram and has been in use going back decades: https://www.rcem.ac.uk/RCEM/Quality-Policy/Clinical_Standards_Guidance/RCEM_Guidance.aspx?WebsiteKey=b3d6bb2a-abba-44ed-b758-467776a958cd&hkey=862bd964-0363-4f7f-bdab-89e4a68c9de4&RCEM_Guidance=6
Whilst drug dosing is not overtly a prediction algorthim/decision tool in that the decision to treat has already been made, most pediatric drug dosing, even (especially) in emergency cases, requires calculating drug doses based on weight at time of use. Same for adult oncology drugs and things like low molecular weight heparin, EPO, immunosuppressants. Even an antibiotic like vancomycin is dosed based on weight and then subsequent concentration measurements (https://metrosouth.health.qld.gov.au/sites/default/files/msh-vancomycin-guidelines.pdf) - which while a heuristic is based on pharmcokinetic calculations. i.e. continuous variables made into a heuristic. (indeed look at that link - its a complex heuristic. Plugging values into and app could be easier to use with alot less time spent than reading the heurisitc!)
So physicians can and do perform time of use calculations based on continuous variables - even in emergent situations, all of the time, day in, day out. The question is then, why do they do it for some things and not for others? Probably a combination of necessity (i.e. in pediatrics you simply cannot ignore body weight when writing a prescription and the adult drugs I mentioned all have narrow therapeutic indexes), matching previous trial designs for comparability, tradition/habit and perhaps a lack of awareness of alternatives in some cases.