I don't think it's a dns resolver issue. I'm intentionally using 8.8.8.8 to prove the point (same results with other mainstream services like 1.1.1.1 by the way):

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$ nslookup google 8.8.8.8

Server: dns.google

Address: 8.8.8.8

Name: google.

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$ nslookup google. 8.8.8.8

Server: dns.google

Address: 8.8.8.8

Name: google

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(Edit: formatting).

It's the local client not the resolver. Try "ai."

I had no issue with ai, I'm referring to google, see the nslookup outputs I pasted above.

Or use a worse DNS resolver. Your ISP may be trying to cash in on DNS names that don't resolve / ain't found by instead sending you to another website that pays the ISP a small fee.