Not sure I agree with the above statement. You have received numerous, quick, accurate responses to the issues you posted about. It speaks volumes about this amazing community of volunteers that are willing to share their experiences and knowledge that they have accumulated over the years.
Home Automation is an ever changing field of technology, and it does take a little while to come up to speed on the differences between the various communications protocols, and the various manufacturers' device product lines.
While it is obvious to you, to the rest of us, we need additional information to assist in troubleshooting. The Sylvania app implies that the bulbs you chose are not Zigbee bulbs, but probably Bluetooth or possibly WiFi. In the Hubitat Device Compatibility list, it is clearly stated that Zigbee is the required communications protocol required to use Sylvania Smart+ A19 RGBW bulbs.
I agree it would be nice if Hubitat listed all of the specific model numbers from Sylvania that meet this specification. However, Sylvania/Osram has been creating these bulbs for many years now, with product lines changing ownership and model numbers changing multiple times. It is not really realistic to believe that the relatively small Hubitat team has access to every product from every vendor that they have ever made. Thus, it is very challenging/impractical to keep the documentation accurate to that level of detail.
Please be aware that Sengled also makes smart bulbs that are designed to work with either Zigbee or WiFi. Hubitat only works with Sengled's Zigbee bulbs.
For example, these are Zigbee bulbs that work well with Hubitat.
https://www.amazon.com/dp/B01N7I4X94/ref=twister_B09BKB3KGN
No, it is closed source.
Hubitat's documentation is actually a WiKi, that community members can request access to submit changes to. Thus, the documentation is fairly 'open'. Please feel free to help keep the documentation up to date as you find errors, omissions, or out of date material. This is the power and strength of such a strong community, and we welcome you to become a part of it!
I am not sure what level of experience/proficiency you have currently in the home automation field. Thus, it is difficult for me to accurately 'target my audience'. I hope you share more about your experiences and become an active member of the community. Please realize that Hubitat does enjoy a passionate following here in the forums. In addition to thousands of active community members, we are also very fortunate to have the Hubitat Team be very active as well.
Again, Welcome to the Hubitat Community!