I’m a complete beginner and currently doing StrongLifts.
You could certainly squeeze the 3 days into 4 during the beginning of the program. I started with the just the bar and could fly through the workouts for the first several weeks. However, once the weights start to get heavy, which for me was around 245ish on the squat , the extra days of rest have become critical. So much so that I view weekends as mini celebrations for kicking ass during the week and an opportunity to sleep and recover.
Another factor to consider is the time involved. If you’re already tight on time SL may not be the most efficient program for you. At light weights workouts can be done in 30 minutes no problem. However, now that the weights are getting hard for me, after stretching, completing all the warm up sets, then the 5X5 work sets, Im sweating my ass off in my garage for 60 minutes plus.
I actually really like the program. It’s dead simple, and it feels great to make tangible progress. But Iike I’ve said I’m a beginner so take my comments with a grain of salt compared to other advice you’ll receive.