While some of the posters are tackling the loss of constitutional rights through judicial limitations of those rights... Which is part of the design of those rights... I would like to highlight that you are correct in pointing out some unique flaws in the American system. Utilizing non-violent drug convictions to deny voting rights targets vulnerable populations and make your voting base generally comprised of wealthier individuals and exaggerates the power of racialized police targeting. Both the US and the UK have this... But not all democracies practice this. Many countries have zero restrictions based on felony conviction or imprisonment. The intersection of drug use, rights and the churches involvement in 12 step programs are also not living up to a lot of modern discussions of ethics or the separation of church and state implied in the design of the US.

Practice and design are two different things. Canada does not have a specific division of Church and state anywhere in the body of law. On paper its got an official religion. In practice however it is incredibly secular and most of the citizens believe whole heartedly that religion has no business in government which is backed by a constitutional freedom of religion. The use of 12 step programs is being challenged and dismantled as a breech of these rights. ( https://www.google.com/amp/s/www.cbc.ca/amp/1.5391650 )

The 2A rights particularly are more difficult to engage with using international comparison because there are only four democratic countries that have a specific constitutional right to bear arms and two impose further restrictions and deference to law inside the body of right itself. The only countries with so broad a written constitutional right to bear arms is the US and Guatemala. Other countries that guarantee those rights do so inside their body of regular law which means that right is not elevated. It can be more easily ammended and changed by sitting bodies and it interacts with criminal law and licencing programs more fluidly.

This structural difference is important. It is supposed to provide additional protections. However the cultural nature of guns is under public challenge. The US isn't nessisarily playing by it's intended design because in part from a written standpoint the 2A is a mess. The issue with old democracies is that they were kind of in Beta and the wording of those laws do not match the modern standardized code that comprises the body of active civil and criminal law and that leaves more than normal room for personal interpretation. The cultural nature to hold the constitution as a holy document that cannot be updated for function sake for mostly sentimental reasons means that you basically don't get the last word on these things or a solid grasp of whether something is constitutional until a Supreme Court majority interprets the archaic document in basically whichever way they please. There are logistical issues with treating law like a precious artwork instead of a practical tool.