Former Safari engineer here.

There is not one iota of truth to that statement.

Said more neutrally, Safari is far behind all the other major web browsers in standards implementation and dev friendliness. As an outsider, I also assumed this was to preserve app store revenue. If it's not, could you share some insight on why it happens?

“Far behind” is perhaps an overstatement, especially today. Things have rapidly improved in recent years, with a _lot_ of time and energy being spent on spec compliance and interop (see https://wpt.fyi/interop-2024).

Why has indexedDb been handicapped for so long?

I certainly hope it's not true. But I can also understand how it's hard not to be a little salty. After a decade of development experience, it certainly feels like IOS Safari has consistently made life more difficult when developing web apps.

Don’t believe ones lying eyes eh? There is plenty of reason to believe this may be the case and your refutation offers nothing to make anyone think otherwise. I am willing to listen if you’re willing to speak?

They aren’t handicapping the web. They are just deliberately handicapping their own ecosystem to prop up their App Store revenue. There is a lot in Safari that is disabled behind flags on iOS.