I think defending religious freedom has always been more important that criticising religion. Particularly for atheists.
I agree. As long as religionists are not allowed to impose on others, their influence seems to wane naturally -
The entire purpose of organized religion, and most ideas and values at the heart of Abrahamic monotheism, is to impose upon and control others. It is well designed for the purpose which is why it inherently promotes authoritarian imposition and control whenever those ideas are taken seriously. This impact of religion only fails to arise among people who do not actually take those ideas seriously and defer to secular ideas and ethics, despite any superficial group affiliation they might retain.
These religions are inherently aggressive and seek to gain ever more control, even without any opposition. They are not merely defensive, and do only aggress when provoked. Thus, active opposition to them does not increase their attack but is required fight back their ever aggressive tendencies.
The only reason that religiosity is waning currently is because of the modern world created by a science-fuel enlightenment in which religion was opposed and its effort to control actively resisted. Open philosophical and political critiques of religion were a crucial part of what allowed for modern secular societies rather than the theocracies that religions inherently push for.
kids brought up in strictly religious environments who can mix with non-religious (or differently religious) kids don't take long to grasp that their parent's beliefs don't confer any special advantages, and that their "differently religious" friends are neither monsters nor sub-humans.
Not true. Most kids brought up in strict religious environment maintain or at least return to those views, despite being emersed in a modern pluralistic world.
The biggest attackers of the religious are the religious. Those most open to other religions are precisely those with minimal actual belief in their own religion beyond its superficial trappings. Exposure to critiques of religious ideas and ethics are often what lead many people to either leaving their religion or becoming less religious than they were raised, and less religious means less likely to support violence against other religions.
Criticising religion tends to reinforce it;
The evidence strongly shows the opposite. Religion ruled and grew ever more in power for centuries, and during that time there was almost no open criticism of religion, except from one religion toward another. Over the last 500 years open criticism of religion has been ever increasing and religions rule has been ever weakening. This covariance is not only true over time but between places. The more a country or a region withing a country has open criticism of religion, the more religions influence is on the wane.
religionists love to claim that they are being persecuted,
Yes, and it is all invented bullshit that they do even in the absence of criticism, showing that real criticism has no impact on how much the claim persecution, which is really only an excuse to "fight back" which really means oppress others, which is part of the inherent authoritarian aggression of religion that must be opposed or it consumes as it did for most of human civilization.
and tend to double-down on their illogical beliefs when exposed to logical criticism.
This is somewhat true, but it is a short term effect, and they don't really increase in their strength of belief, they just double-down on their terrible attempts at justifying those beliefs.
Remove the barriers to a non-newtonian fluid flowing through a funnel, and it will slowly drain away. Try to force it though, and it becomes rigid and persists for longer than it would if left to its own devices.
Yeah, that is the danger of analogies, having one seems like "evidence" but it isn't, because the evidence is what determines whether an analogy is valid, and in this case it isn't. Criticism is not a barrier to keeping religion from flowing away, but rather a barrier keeping the never ending supply of fluid of religion from filling into the funnel in the first place. Your analogy wrongly presumes a very finite supply of religion (fluid). It is infinite (as long as humans exist), thus will never "drain away", and designed to aggressively find new ways to be the only thing allowed in the funnel. Reducing how much religion is in the funnel is done opposing its pathway into the funnel and poking holes in the funnel to increase how much is leaving relation to how much is getting in. Support for those efforts to divert the fluid from the funnel and poke holes to let more drain out only comes with open critique that exposes the inherent opposition that fluid has with the other things (reason, progress, liberty, equality, justice) that most people claims to care about.
