As a source of non-questionable/non-arguable information such as the Earth being an oblate spheroid and it's explanation, the distance to the moon or the effect the moon has on the tides then yes Wikipedia could be trusted as a source of scientific information.
However once emotive subjects which can draw polarised debate enter the discussion forum such as politics, global warming, religion, migration, EU membership etc, etc then NO, it can't be trusted as it's too accessible to those with a specific agenda to corrupt the information in favour of their argument so one has to be circumspect where choice of information source is important.
The same applies to news sources. I tend not to swallow the garbage put out by the left wing press such as the Guardian/Independent et al and the same applies to news from that of the right or news put out by both the BBC and ITV as from my past experience of them reporting events I'd have to say they're both biased and not to be trusted.
Instead I try to ascertain as many facts from news sources/information from beyond these shores through news sources which have no link either through prejudice or bias toward the UK's incumbent governments, that way I can draw safer conclusions than information from the British media or such as Wikipedia.
One only has to look at the announcements by governments of any rosette colour to recognise that they will quote and manipulate facts and figures which support their agenda rather than give a true picture of what is really happening so for that reason I prefer to do my own research and make up my mind as to the information accuracy.
The same applies to polarised posts on forums such as this. Most posts are just opinions with facts and in many cases adversarial which again is understandable so I will as far as I can look at the post content and see if there are valid points or if it contains information that could be verified through research.
As they say, you should never believe what you read in the papers' which is true, the same applies to forums and news media outlets alike...never trust any of them unless what they say can be backed up or verified by independent sources.