Folders are not as comfortable as 'big wheel' bikes, although those on 20" balloon tyres come close.
Commuting is hard on the bike, not just the miles day in, day out, but the stopping and starting means accelerated wear on brakes, tyres and drivetrain.
The bike will usually be loaded with clothing, lunchtime sarnies, laptop, etc.
A quality push bike folder, such as a Brompton, can do the job.
They start at about £800, closer to £1,200 in full commuter spec.
A generic Chinese folding ebike for £700 does not have the quality for reliable commuting.
The fold itself is another consideration.
Folding ebikes are still heavy bikes, and the folded package is OK for lifting into the back of a hatchback, but no use for regularly getting on and off trains and public transport.