Yeah, I know of an identical incident in my country. Some police officers from my country stop a bus and arrest a man with his phone. Later we found out that the man was involved in gambling activity and at that time he was holding 22 Bitcoin in his mobile Bitcoin wallet. I am not sure if that man was dumb to do that or not conscious enough to carry his Bitcoin within his mobile phone.
I don't think there is nothing wrong with him having his bitcoin along with him always but the truth is that the country is messed up and I don't know your country but if the guy can prove that his winnings are from gambling then I think their shouldn't be any reasons to hold him down except gambling is illegal in your country .
On the other hand, if someone already has over 22 Bitcoins in his possession, then what really must have hindered him from having a hardware wallet?
Well I'm sure only the victim can answer perfectly for himself but whatever the case might be, we should learn how to trade with caution while handling Bitcoin and cryptocurrency in general especially if it has restrictions in our country
At some point I prefer not to go public with anything that will announce me as Bitcoin or cryptocurrency user this is because in my country, Bitcoin is not legalized yet but everyone use it just like 🌿, so if you leave in such a country as mine, the best possible measure will be to avoid physical exchange or casinos because this is red spot activities and must be done underground to avoid possible suspicion that could lead to your privacy invasion by overzealous security personals, and just as you have said, having a 22 bitcoins outside is a big risk because the ops become vulnerable to attack I suggest, the best possible practice should be to leave you wallet keys somewhere accessible, but don't carry wallet apps on your mobile while travelling or outside.
You don't know when you can come across some corrupt policemen who don't know the rule of law coming to search your phone, even though they don't have such right against the citizen, to search any citizen's phone you need a warrant.