When I registered a domain with my surname in it, the registrar had an automatic process in place that checked for this trademark and took away access of the domain. So far so good. The problem was that the registrar and its support then ghosted me and also never refunded me for the money already paid to lease the domain for a year. Overall it was a bad experienced with bad communication that made me switch registrar (note: this was a different registrar than mentioned here).
I think one of the problems is that as more and more individual consumers buy domains, certain legal processes and automation are not ready for that. A good registrar should anticipate that an individual private consumer may not have the legal experience or knowledge to deal with just being hit with something they were never explicitly warned of.
I don't think this is good.
Trademarks are country-specific, not global like domains. Further, within a country trademarks are only valid within the scope of certain classes, which means:
* There will often be more than one trademark holder of even non-surname trademarks.
* You can't trademark a surname to prevent its use generally, you can only restrict its use in a narrow sphere.
I understand why domain registrars automatically overenforce their country's trademark laws (they can't deal with the legal complications that will result from them not doing so), but it's very much not good that someone like you can get to a domain for your surname first and be told you can't have it in case the trademark holder (for which class???) might want it.
Domains are also subject to local law! For ccTLDs, it's usually that of the country in question; for gTLD, to my knowledge the US has effective jurisdiction (through ICANN) over at least some of the popular gTLDs such as .com and .net.
"Local law" in this case doesn't just include actual laws on the books, but also the risk and cost of getting sued by either a trademark holder or a non-trademark-infringing domain owner.
This is exactly the type of issue that people usually don't consider when picking a TLD, vanity or otherwise.