PLEASE, do NOT follow this advice, PLEASE:
1."Random photos are better than screenshots"
3."semi-vague messaging on a landing page is more powerful than clear and detailed messaging"
No, the advice is not "random photos" and "vague messaging" but "Do A/B tests ASAP" - as soon as you have enough traffic to do them (yes, there's a threshold, under it you're playing dice, not A/B testing).