#curl sometimes fails to access some servers. In most situations the problem is not in curl itself but on the server side. Example:

1. Fails: curl https://www.radissonhotels.com

2. Works: curl -A 'Mozilla/5.0 xx Chrome/119' https://www.radissonhotels.com

3. Fails: curl -A 'Mozilla/5.0 xx Chrome/118' https://www.radissonhotels.com

4. Fails, too: curl -A 'Mozilla/5.0 xx Chrome/1189' https://www.radissonhotels.com

Perhaps they perform #filtering to obtain improved #security? It's hard to tell, but any serious attacker surely knows how to spoof the user agent string and bypass such simple #regex