Trimble has indicated that they intend to keep SketchUp Pro around with new versions. Forum opinion is that these updates will continue to be yearly, likely appearing mid-November.
Remainder is my personal speculation:
Sketchup Pro, purchased at $699 US and maintained (including any newly released updates) for $120 US/year is a good business model, ensuring a steady income stream as long as one continues to provide value for the yearly maintenance.
SketchUp Make, in isolation, is not a good business model unless they can find advertisers to make it adware.
Trimble has likely found that Make was too close to Pro in capability such that many people use it commercially (despite the non-commercial only license), thus depressing potential sales of Pro.
What to do? Do no more development on Make, but keep the last version (2017) around for people who can’t rely on an internet connection for their new product: SketchUp Free.
So now we have Pro as the most complete package, Make as an option for off-web use, but not maintained, and Free - a more limited version, but web based.
Hmmm. How to give Free users a glimpse of the power of Pro, and give them a version that is OK for commercial use? Enter Shop! Priced significantly less than Pro, but featured enough for serious use. Biggest drawbacks compared to Pro: No Style Builder, No Layout, but most critically, no Extensions!
Of these 3 drawbacks, it’s the no Extensions that is most difficult, currently likely impossible, to provide with a cloud based SAAS.
So I expect the SketchUp Universe going forward will be:
- Make: Frozen in time - no commercial use
- Free: Basic modeling, web based, no commercial use
- Shop: Very Capable (once they iterate a bit), web based, commercial use OK
- Pro: All capabilities, not reliant on the web, commercial use OK.
If Trimble manages a version of Layout that’s web based and somehow manages to let the existing extension code base to work on a web based SAAS, then all bets are off.