How to say that something used to be advanced and important though not any more?

Question

I want to express something like

Even though something appears to be outdated or incompetent from today's perspective, it indeed brought many innovative contributions at the time it came out and has been influential to the subsequent products/works.

For instance, even though the operating system Windows 95 is now outdated and obsolete, but at the time it came out, it was an revolutionary system, that had many merits ahead of its time, and has affected many afterwards systems.

I didn't mean to be so wordy, but I couldn't find a compact way to express similar meanings. Should I say

1. Though Windows 95 is not the best system now, it had many advantages at its time.
2. Though Windows 95 is not the best system now, it has been influential to many other systems.
3. Though Windows 95 is not the best system now, it ________________.

Answer 1

I like revolutionary, like you mentioned.

revolutionary

1. a : of, relating to, or constituting a revolution
   c : constituting or bringing about a major or fundamental change

So for example

Though Windows 95 is not the best system now, it was revolutionary when it came out.

Notice that by definition, revolutionary implies that something is influential. Also, when you call a product revolutionary, it is often a product that has many positive qualities and advantages.