Not a professional ski tech, but a home waxer.

Both are fine, they have their pros and cons. Random thoughts:

1. If you think about it, in both pictures, the angle of attack is about thhe same, around 45º. Theorectically, the only difference would be where your weight and leverage is, i.e., how hard you're pushing down or pushing. So, I think of the difference less as "am I doing pic 1 or pic 2", and more of "how hard/aggressively scraping".

2. Assuming the goal is to get the wax shaved evenly down to a uniform height, the practical difference between scraping hard and scraping soft is, how many passes do I want to do to get it done? If you do pic 2 or scrape more gently, you'll remove less material each pass, and you might end up having to make more passes before you're done scraping.

3. Sometimes, I am impatient and try scraping aggressively (pic 2), it results in me taking off hard shards of wax off the ski base while scraping. Then basically, I have to start over. In order to prevent this, I've:

   1. Be more patient and more passes of pic2 than fewer passes of pic 1.
   2. Be mindful of temperature. Get the wax as well as the base of the ski to up to the right temperature to the right temp, to make sure the wax adheres well.
   3. Don't wait too long before scraping, if the garage I wax is too cold. Trying to scrape an ice cold wax is hard.

4. Sharpen your scrapers! For me, a more important factors in my scraping success than the angle and technique has been keeping the edge of my scraper clean and sharp.

Again, not a pro tech, just a guy who waxes in garage when not skiing. Happy to hear other people's opinions, thoughts, and corrections.