You missed the crucial point.
My statement is that the ISP can find this out / knows this.
Your statement is that only the ISP can.

That's a huge difference.

You can't answer this question with a generic "only X can do Y".
It depends on the whole situation. In some theoretical circumstances every single person could find out which wallet is being used (e.g. weird individual locktime set).

This most probably is not the case for OP, but a generic answer to such a question is simply wrong.

With a VPN, the VPN provider for sure knows what kind of wallet you are using.
Without, the ISP does.

With a VPN, the VPN provider for sure knows what kind of wallet you are using.
Without, the ISP does.

While Tor definitely might help here, a full node could be prohibited from connecting to the bitcoin network via Tor by exploiting the built-in DoS protection. Resulting in either a clear net connection, a tor-only connection (excluding the clear-net bitcoin nodes, resulting in 2 separated networks, at least for a maximum of 24 hours which would be easier to "control" privacy-wise) or no connection at all.
SPV wallets via Tor are a different story again. If we are talking about a SPV wallet building on top of bitcoinj, that's probably the only thing one could determine using the privacy leaking bloom filter.

I am not saying that it is definitely possible to find it out. Especially not with Tor. But it's not impossible.

However, since OP asked whether someone can find out if he is using blockchain.com or electrum, i heavily doubt he even ever heard of Tor.
And in his case.. an institution definitely could find out which wallet he is using. A random stranger on the internet, can't.

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If you don't know anything about the topic, better don't talk about it.
Or at least don't make it sound as if you know anything.