Will not you be so kind as to explain the difference between burglary and 'reverse engineering' of the transport protocol?
And you in this case are different from the 'carders' stealing money from other people's accounts?
I read through all 7 pages of oddly-translated-from-russian comments on mql5.com. The only way I could charitably give them a point is if there's some terms & conditions that brokers sign when they obtain the MetaTrader platform from MetaQuotes. If they state that they won't allow third-party access or something like that, then I suppose maybe the BROKERS could be in violation of a contract with MetaQuotes. Please note that I'm not saying this is the case, but just that it's the only potentially valid point in there I can think of. And even that is 100% conjecture. Regardless, the official MetaQuotes stance on that thread is so odd that I really can't comprehend it and wonder what I'm missing.
On to your question (accusation?): if Myfxbook reverse engineers a protocol, it is NOTHING LIKE burglary or carders stealing money. If you honestly don't understand this, now you know. Reverse engineering a protocol happens all the time in technological circles, and there is nothing inherently wrong with it. The only thing 'wrong' with it is that it's an undocumented feature, which leaves it open to being changed or removed at any time.
A couple years ago, I started a company built on some products MetaQuotes offered. I thought it was a good idea. I let them know about it and got a couple responses, and suddenly everything went quiet. I finished the product, it all worked technically, and then, what do you know, MetaQuotes put out essentially the same thing. That's been my experience dealing with the company. I'm not saying they stole my idea as they were working on it in parallel, but they seemed to have no interest in working with me even though having me incorporate their system would have been a win-win.
In this case, as has been mentioned numerous times before, if MetaQuotes offered an API, they could even charge a reasonable amount for it and likely all these third-party companies like Myfxbook would be happy to use it. The companies that usually do best are the ones that provide an open ecosystem for use of their products. This is standard with pretty much every software company out there, from Salesforce to your credit card processor to Microsoft to ... well, everyone except MetaQuotes. Even Myfxbook has a published API to encourage third-party use and development.
The official MetaQuotes comments from Renat seems to be this (translated from Russian):
Not everyone has noticed how changed our approach. From the creation of a free infrastructure for the other, where a bunch of third-party companies receiving of benefits from ecosystems created by us, we moved on to note just in their own hands. Our services are developed and launched new ones, so wait for news.
While third-party companies have received benefits from MetaQuotes, MetaQuotes is also receiving benefits from third-party developers. The more tools like Myfxbook there are, the more attractive MetaTrader becomes compared to the competition.
The real point here is 'our services are developed and launched new ones, so wait for news'. I'm not sure if this is news of a documented public API, or news of competing services, but either way I guess we'll find out soon.