I operate in the gym niche in Poland.
My beloved Polish law prohibits cold mailing and cold calling, unless you have explicit and documented consent to transmit commercial information from the recipient.
(no, I can't call and ask if I can offer someone something - then I'm breaking the law)
The only way to get around this is to send cold emails to general addresses, e.g. "[email protected]", where there is no visible personal data. I also can't do it en masse, because there are no lead scrapers available in Poland that work properly, because entrepreneurs' data are not as easily available as in other countries or outside the European Union. The next problem is that 7/10 of the gyms in a given city are large franchises with dozens of other facilities throughout the country.
I only have to focus on smaller businesses, which are relatively few in number, which, combined with the fact that I have to collect this data myself, means that my outreach is slow, etc.