I'm fairly certain HubSpot's audience wouldn't trust me as far as they could throw me before I was featured on their blog. Not because I am a shady character, (I'm not, I swear) but more so because they just didn't know who I was.
If we have a guest blogger appear on our blog at IMPACT, it's because we trust and value their expertise, and we want our subscribers to do the same.
With guest blogging on the chopping block, it's likely that businesses will become more selective over who they offer a spot to on their blog to avoid endorsing the wrong crowd.
If anything, this selectivity will increase your credibility that much more. If someone decides that your content is upright enough to serve as a representation of their business, you've earned their seal of approval and hopefully their audience's as well.