Been dealing with this exact headache for years across different companies. The platform vs GA4 discrepancy is real and honestly never goes away completely.
What works best is setting up a blended attribution model. Take Meta’s numbers, GA4’s numbers, and create a weighted average that leans slightly toward GA4 since it’s usually more conservative. I typically use 60% GA4 and 40% platform data.
Be consistent with whatever method you pick. Document your approach and stick to it so you can track trends over time. Your CEO will care more about month over month improvements than perfect attribution.
Also worth checking your UTM parameters and conversion tracking setup. Sometimes the discrepancy comes from technical issues like Safari’s tracking prevention or iOS 14.5 changes that hit Meta harder than GA4.
For reporting to leadership, I always present both numbers with a clear explanation of why they differ. Most executives understand there’s no perfect attribution once you explain the technical reasons.
One more thing - if you’re doing cross-device conversions or have a long sales cycle, GA4’s data view reports give you better insights than the standard attribution reports.