Is a powered car tire inflator suitable for road bike tire inflation?
Buy a floor pump, also known as a track pump, instead of an automotive accessory.

A track pump will take about the same time to top up your tires as a small car compressor, and has an advantage of not needing electricity at all.

You still need the on-bike pump for punctures while riding, but in the garage at home a track pump works very well.  I ended up carrying a smaller track pump on my bike instead of a minipump.

Do get one with a gauge - doesn't matter if its analogue or digital but estimating tyre pressure by squeeze isn't ideal.  A track pump will last you decades, where the small tyre pumps tend to fail in a few years.



Incidentally - I've tried to use my big track pump to add some air to a car tyre, and after 10 minutes I'd raised it from 20 PSI to 22 PSI.   If you want to inflate car tyres as well, get both.  One pump will not do both jobs well.

My car tyre compressor stalls out at around 70 PSI  despite being "rated" for 175 PSI - there is no way it can pump up a road tyre and if I did, would have to finish it off with the hand pump anyway.