I 100% agree with plainclothes that SEO as the reasoning for this decision is a mistake.
Still, that leaves open the question of whether it is a good idea from a user experience perspective.
"Clutter" is a rather loaded term, which implies that more content must be a bad thing. However, that is not always the case.
Lots of prominent, successful sites could be derided as "cluttered". For example, open almost any news page and you will find something chock full of content. But this is a positive for the user, since it allows instant access to a wide variety of content.
On the other hand, I find that much of what is lauded as "clean" design is actually poor in terms of usability. Apple design has many fans, but I find that many of their products suffer from key functionality being hidden and hard to discover. On the iPad we own, one has to hold down a button to perform one key function, swipe with three fingers for another, etc. None of these things are discoverable from looking at the screen. Our toddler often discovers functionality we never knew existed just by making random gestures on the screen. Is this good design? It is far from clear to me.
I would say:
- Avoid "clutter" in terms of unnecessary content.
- Don't hide something useful just to make the design look "clean".
The latest blog and forum content may well be useful information on your landing page. It would depend on your site's purpose and the needs of your visitors. If a large percentage of people landing on your page are interested in the blog or forum content, or your want to direct them to those locations, then it is probably a good idea. However, it may not be if they are peripheral to the site's main purpose--in that case it may distract from the important information.