Supporting oldest Apple platforms for software development

I understand's Apples goal to use latest OS and latest hardware to reduce issues, have new features, improved performance, etc., But Apple should not drown users using old devices and they are not rich like Apple and some rich peoples to buy New devices every year or few years! Some users use single device for their life time! Money is still needed! When money goes off Apple is number one In some I know!

Also have to note due to this issue everybody is jumping to web application which is not really useful to have all applications in Web browser! One cannot easily access device and UI features In web browser application, due to security issue! Even in web browser there is no cooperation among vendors and makes users suffer!

I want clear guides on how to develop for old devices! Can i use latest Mac to develop or i need old Mac to develop? Which Xcode Versions and other tool versions are required to develop for older devices? I need an Apple website that tells all these! If you take time for to developing that web site at least provide it in the comment for now! If you provide a link i should get Information easily and not struggle!

Appreciate if you reply!
If apple not responds properly then I will also be forced to move to web application for some, where all devices support, no syncing issues, no one can reject the application, low quality applications since cannot review, no need iCloud and always online! No one can spy since own server! Internet is available in most places! Apple may loose that 30% earning from developer! Can we use swift to develop for older devices, i'm not sure? How many languages a developer as to learn Java, JavaScript, C++, Kotlin, Python, PHP, etc., ? How many SDKs one has to learn Swift UI, Divi, Bootstrap, Angular OS, One UI, Kotlin UI, MIUI, Color OS, Apple AI, Samsung AI, etc., ? I hope Apple feel it !
Apples good strategy will be to develop low cost devices with quality parts and quality software and make sure everybody able to buy! Make Swift the only language for developing application! Competitors will vanish and will create cooperation! All developers will be happy! I feel Apple can do it have lots of money!
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Any reply?
Any reply?
If nobody want to reply what can i do? Just changing this forum to fancy and beautiful is not enough have to reply right? It is up to you all!
Apple even though you don't reply not a problem, but want to say something about Flutter which tries to solve things similar to Java in older days supporting all devices! Another new language called Dart that runs in a virtual machine? Sorry I'm not for that! People wasting time to develop new languages and trainers and developers wasting time to support them! Nobody is going for one big cooperation that reduces all peoples sufferings! Google always goes in wrong ways and also spies users! Let's make Swift the only language! I want only single platform and single language that is designed and developed in cooperation by all the peoples in the world! I will not waste time for other platforms! Rather I can spend that time for a thing that benefits whole humanity!

Apple never spies users private information and creating lots of new technologies for privacy! I'm proud of Apple!
Other than Apple! Google, etc., companies only delays humanity progress! It is the truth!
Anybody can reply to my first question!
Supporting oldest Apple platforms for software development
 
 
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