Firstly: I liked Delphi a lot; learned it a long time ago.
Straight risk avoidance advice:-
You need to install the Delphi software on a completely dedicated system that you never plan to reset; and image back it up; and hopefully that will work.
And install the software on a Virtual Machine and back that up.
And/Or always renew the subscription if the new features make any sense to you or not.
Do these things and you will be Ok.
My experience was:
I am programming as a hobby; even so - I don't like to commit a huge amount of my personal evening and weekend time to software with a toy license that restricts what I can do with it.
In 2017; Delphi started to look good again; I got the starter edition; really liked it; found it useful; thought why not support the developers; and upgraded to the commercial version at 10.1; also purchased a number of really nice plugins; (used Delphi in my spare time project for a year or so); very happy with the results.
Stopped using it for a while; because my project was finished.
I also messed around with Delphi on a couple of my systems while playing with mobile apps and Macs; found it much less useful there.
My main focus is windows desktop not mobile; I was playing around with new pre-release versions of Windows; I had to reset those systems when they got out of hand.
I ended up unable to reinstall 10.2
(my third party components need that.)
So I contacted support; and was knocked back; with a cold email.
I guess the licensing methodology may be legal (not a lawyer); but it does not seem fair or reasonable to me.
I have written a lot of Delphi in projects I can not rebuild; I own several third party components that are now useless to me.
The current version is I think 10.3; I was subscribed up until 10.2.
Other feedback
I think Delphi is good for Windows desktop programming; especially for GUIs that connect to data bases; nothing like as exceptional for Mac or Mobile.
With respect to those databases you used to need the Enterprise version to use MySQL etc; as the lower license agreement did forbid the use of database services; only allowing local data.
I ended up spending many enjoyable hours learning or re-remembering how the database connections worked in Delphi; and figuring out how my third party components all worked; then enjoyed gluing them all together in my programs.
Where I am now:
I could purchase the latest Delphi and update all my components; for no real benefit to my project; or I can learn to like .NET core and get translating. The third party components I used; are also available for .NET; and there are thousands of open source packages for .NET as well. Not so sure about the GUI.
How do they stop you?:
To be completely clear; because that company likes to be fuzzy about it; I have a valid license; serial number; invoice; and online account (which I really need to delete); I am blocked because I re-installed the software too many times.
Where too many; was not very many; and was not even concurrent.