As a user for both products, I'll answer each point one by one:
- Ease of use: AVG is probably a winner here. Both GUI are very clean, although BitDefender's main interface with movable shortcuts and tools can get a bit messy. AVG shortcuts are clear and static, you don't need to search much for anything.
- Impact on hardware performance: I'd say tie. AVG has the option to set antivirus to scan only accessed programs, and BitDefender has similay (not quite the same) options. Both can get very fluid and quick, and booting time on my laptop are almost the same.
- Most available features: AVG wins here. BitDefender doesn't include "many modules", but is solid enough. Still, their modules aren't as configurable as AVG, and definitely does not have a secret cave for configuration like geek:area.
- Core protection (malware and heuristic engine): both offer decent protection. I've found ADT (Advanced Threat Protection from BitDefender) to be more sensitive to suspicious activity/changes. This wouldn't necessarily mean it's "better", but more sensitive for sure. Haven't had the time to make specific malware tests, but they perform similar, although I cannot say much about AVG technology on dealing with new/fresh malware (Bitdefender never failed me here).
- Internet protection (web filtering, anti-phishing, anti-spam, browser extension): IMO BitDefender is a winner. I get daily blocking with surfing the web, on phishing/scammy/shady sites, and after weeks with AVG none of these.
- Proactive protection (anti-exploit, behavior blocker, IDS-HIPS, sandbox): as for Behaviour Blocker I've talked already, and I have never personally seen anti-exploit or sandbox with these two products, or I haven't seen the first one in action.
- Network protection (firewall, anti-botnet): AVG offers a deeper personalization for network protection and botnet issues, while BitDefender does this job quietly in the background. Also their firewall offers no notifications on default (you can enable them but then every single things displays a pop-up and drives you insane).
- Ransomware protection: both products offer "protected folders" module, and allow to block/allow specific applications to modify these folders. AVG gives a little more tweaking options, while BitDefender doesn't; but it offers Ransomware Remediation which detects ransomware activity and automatically backs up affected files, while will then restore after the malware has been blocked.
- Banking and payments protection: decent similar protection.
- Machine learning and A.I. capabilities: haven't invested myself enough into these as to offer a solid argument.
- Privacy protections (VPN, anti-tracking): both products offer these. As for VPN, both are powered by somebody else. Anti-Tracking in BitDefender allows privacy protection online. AVG also offers confidential files shield which protects sensitve documents which may contain personal info, passwords, etc.
- My privacy (GDPR, data handling, privacy policies): BitDefender is Romanian, AVG is Czech. None of these belong to the five eyes, but each handles privacy according to their own terms. Never had any issue with BD here. AVG/Avast we all know what happened, although they claim to be clean now, it's up to everybody.
Both are solid products in their paid versions. You can't go wrong with any, just make sure to tweak them to preference.