This is not the same as the Lucy Connolly case at all. She pleaded guilty to a serious offence and was jailed.
There are rules about bail. It’s all explained here:
www.cps.gov.uk/prosecution-guidance/bail#c8
Where a person is charged with an offence of manslaughter, rape or a serious sexual offence, and has previously been convicted in the UK or court of an EU Member State of an offence of murder, attempted murder, rape or a serious sexual offence he shall only be granted bail where there are exceptional reasons, which justify it.
If a defendant has no previous conviction he can be granted bail.
As for Thomas, in considering whether to give bail there is the "no real prospect" test. A remand into custody should not be sought for an unconvicted defendant who has no real prospect of an immediate custodial sentence.
Thomas has a conviction. In 2016 he was jailed for two years after pleading guilty to attempting to kidnapping a man at knifepoint.
He has now pleased not guilty to an offence which he recorded himself committing.
He was arrested on suspicion of four separate things relating to to the incident at sea: destroying ships or endangering their safety under Section 11 of the Aviation and Maritime Security Act 1990, plain criminal damage, criminal damage with intent to endanger life, and conduct endangering ships or individuals under Section 58 of the Merchant Shipping Act 1995.
Two of those four carry the maximum sentence available under English law.
So far he has been charged with one count of criminal damage along with an offence under section 53 of the Regulation of Investigatory Powers Act 2000 (Ripa), for allegedly failing to comply with a notice to disclose a phone pin to police.
The latter can result in a two year custodial sentence or five years if the case involves national security - which, in view of what he has been organising lately - may apply.
I am sure you are aware that PACE requires the police to charge someone within a set time or release them. Further charges can be added as investigations continue.
I suspect there is a very real prospect that Thomas will be sent to jail again and that’s why he has been refused bail.