Why dont you consider option of implementation of your technologies for MetaTrader 4 which is also popular?
Good day,
MetaTrader 5 is chosen due to the fact this platform is more up-to-date and has number of new features which are not available for MetaTrader 4. Also, the developer of the platform plans to stop serving the previous version of a platform in near future. I hope this answers your question by itself. Thanks
Are there any other platforms except for MetaTrader 5 which you may start working with in the future?