I believe in part some of the hesitancy comes from the hassles created by techie-level features being made available to the general public.
Someone new to css (or doesn't know what we are talking about now) changes border.width to 'red' (instead of 3px) and then doesn't know why it's all crashing will be contacting support, and they will get inundated with 'help me!' requests, users who don't understand or believe they did anything wrong will holler about how bad the Zenfolio hosting is in other forums (I've seen this happen with another Zen feature, coming from a Pro user in a paid Pro forum).
There is just alot of potential for much negative energy coming from such a move, and yes you could just select a stock theme and put your site back, but the tons of support requests will come, and will have to be staffed to respond to it, or present staff will have to wade through it to say "we don't offer css support, select a stock theme to restore your site".
I personally would LOVE to have full css capabilities. I would love to fix mine up, create different themes for free and others for sale, and offer full customization to Zennies for a fee. But I'm also a realist and see how it could become a nightmare for Zenfolio, and so far they are doing excellent work in everything and hate to see them create a PR nightmare for themselves.
Just my thoughts. And the programmers at Zen are a helluva lot smarter than I, so maybe they will come up with some options to allow full CSS customization that will limit how much the inexperienced can do wrong and become irritated like I did (and still do) when learning CSS.
~Kevin
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