Yes virtually everyone is good or has what I'd describe as 'good general moral principles'.
Nowadays with the media being what it is, just about everyone generally starts falling into approximately the same moral category. 'Rights' and 'Wrongs' are screamed at us through the TV, newspapers, everywhere (as oppose to, say, Victorian times ... where child abuse for example was never even mentioned in society anywhere ever, and NEVER taught or even mentioned, so people had to form their own judgements of what they thought acceptable with less help on a standard definition of 'nice', so some would not be good and not even know it!).
With greater population and things like CCTV, accountability has also jumped massively. With things like criminal records and video and media, being a nasty person has never been just basically so darned difficult to actually do. Be a nasty peice of work, and you're going to have a nasty old life ..
Most people want to fit in and get on - or at least have some friends or loved ones. This makes them conform. 'Good' is probably the ultimate conformity, rewarding you with the most friends/loved ones! It even rewards you with money to spend how you will - as generally nice people will 'get on up a few notches of the career ladder' as literally bosses like them more. Most people have worked this out even if at a subconscious level...
of course there are exceptions to the rule, including nasty people with riches and loved ones .. but I'm talking about the general rules here ..