I think the point is that frameworks can be more effective now thanks to tools like LESS and SASS (it's certainly possible to use Bootstrap this way, at least with the sass translation). Compass is another example of a framework that SASS enables.

Bloat of a hundred framework rules? - None of these will be included if you use mixins and selectively mixin the stuff you need.

Unsemantic grid sizes - Personally, I think this is something where utility trumps perceived "cleanness" of semantic HTML, but if you want to you can use mixins for this as well to hide the grid stuff in your CSS.

Not responsive - SASS and LESS don't do anything specific here, but this is definitely an outdated comment - Bootstrap's responsive grid is probably better than anything you could code yourself without devoting a lot of effort to it.

'div class="span-24"' is no better than a table

Even within the strict scope of CSS this post shows it's age. The phrase above in particular reaks of being written in a time before philosophies such as OOCSS. Additionally, popular frameworks are no longer tied as tightly to fixed-pixel values.

If somebody were vehemently arguing these sorts of points today, I would be concerned that I was dealing with the type of developer who resists change or is opposed to exploring and understanding the approaches of others.