I am curious if this is a positive, negative, or neither here nor there. The analysis was done by Wattpad and it also included that fact that I write more like a journalist above anything else. The analysis was done by taking the first 3,000 words from my YA/Teen fiction novel and analyzing it. It's a new Wattpad feature.
There's a certain amount of subjectivity to this, but on the whole a straightforward style is viewed largely positively in current trend. Especially where you are writing for a YA/Teen audience who may not have as fully-developed a comprehension ability as older audiences.
I'm not hugely familiar with Wattpad - and I've never tried their analysis tools so I can't comment on their efficacy or accuracy, but if your beta readers (if you've had any read it yet) are saying similar things then that would be an encouraging sign.
To find out what
Straight forward writing style
means in Wattpad you might try asking its opinion on other books in the YA/Teen genre.
My first impression of "straight forward writing style" was that it'd be good for a report but that I might want something more imaginative for YA/Teen. But "imaginative" may not be one of their categories.
Take it as a piece of positive feedback from whatever algorithms the Wattpad engineers have cooked up. In today's hyper-competitive publishing world (especially in teen/YA genres) being "straight-forward" is a plus. Most readers won't bother wading through confusing text when there is so much other content available to them.
If you're looking for another fun writing analysis tool, check out the Writing Style Comparison -- it lets you submit a sample and will tell you what famous author you most resemble. I just ran it against the text in this post ... and apparently George Bernard Shaw would have been a hit on StackExchange.